Nextcloud FAQ



How do students and employees of participating institutions register on the website? 
Students and employees of institutions in the bwSync&Share network and the DFN-Cloud log on to the website with their local user account via Shibboleth.
To do this, select the institution (the authentication provider) under Login Options and then enter your local user account and password.
The list of participating institutions can be found on the website
organizations in bwSync&Share-network .
Members of the Helmholtz Centres an find the instructions for using bwSync&Share on the Helmholtz Cloud page.
How do users of external institutions register on the website? 
Users of other institutions register as guests on the website by selecting "Direct registration" under Login option. Then enter their e-mail address and the bwSync&Share password.
How can I reset my password as a user of an external institution? 
To reset your password, go to and select "Direct Login" under Login Option and then click on "Forgot your password? On the next page, enter your e-mail address and click on "Reset Password". A link will be sent to you by e-mail that will allow you to set a new password.
How can I participate in the service as a new user? 

Users of institutions of the bwSync&Share network and the DFN Cloud:
You can register yourself for the service:
To do so, click on the button "Member of the bwSync&Share network" on the website, select your institution and log in with the login data of your home account (user name and password).
Then follow the instructions to register for the service and you will be logged in directly to the bwSync&Share service.
Unfortunately, it is not possible at this time to prevent you from having to agree to the terms of use again after the first login, even if you have already agreed to them during registration.

Members of the Helmholtz Centres:
You can find the instructions for using bwSync&Share on the Helmholtz Cloud page.

Users of other facilities (guests):
A user participating in the service can invite you as a guest to a file or folder by sharing the folder with you. (s. ).
You will then receive a welcome email. Click on the button "Register as guest" at the end of this e-mail. On the page that opens, set a password. Then log in with your email address and this password. You must confirm the terms of use the first time you log in

How much storage space is available to me?
As a user of a participating institution, you have 50 GB of storage space available.
The group admins of our university can increase your storage up to 200 GB. Please contact the local support team (the helpdesk) at your university.
As a guest user, you do not have your own storage space, but can only access the data that other users have shared with you.
How can I receive information about planned maintenance work and incidents of the service?
If you would like to receive information about planned maintenance work and incidents of the bwSync&Share service by e-mail, subscribe to the mailing list bwsyndandshare-meldungen does-not-exist.lists kit edu.

Is it allowed to store personal data?

The storage of personal data in bwSync&Share is permitted.
However, hhe user himself has to ensure that no sensitive personal data within the meaning of Art. 9 of the General data protection regulation, data with illegal content or data that violates the copyright or property rights of third parties are stored.
How can I unsubscribe from the service?

Students and employees of institutions in the bwSync&Share network or the DFN Cloud can deregister from the bwSync&Share service via the website .
Deregistration initiates the deprovisioning process, which is started automatically after an employee leaves an institution (see Within this process, the data and account are then deleted at a later date.
For guest users, the deprovisioning process is started when a user has not logged in for a year.

Tips and Tricks

What do I have to consider when working with bwSync&Share?
Is there a backup of the data?
The bwSync&Share service does not include a data backup.
Since synchronization can lead to authorized users inadvertently deleting data on the server by deleting data on their end device, the service is not suitable for the sole storage of data that is not stored on any other device.
You should therefore create your own backup of your data outside the bwSync&Share folder so that no data is lost if files are accidentally deleted.
Further information can be found on the website Tips and tricks for using bwSync&Share  .
Where can I find a user manual? 
You can find a comprehensive English user manual for operating Nextcloud - both via the web and from clients - here
How can I install the client? 
How do I share a folder or file with another user?

To share a folder or a file with another user, click on the sign with the three connected dots to the right of the file or folder name and then select "Share" from the menu that appears on the right.
Then enter the user's full e-mail address in the input field that says "Name".
(Autocomplete is disabled in bwSync&Share for privacy reasons).
Then the name of the user known to bwSync&Share for this e-mail address will appear below it and you click on the button with this name. After that the user will receive an e-mail informing him/her that the folder or file has been shared.
If bwSync&Share does not yet know this email address the button "Invite guest" appears.
Click on this button and a window appears in which you enter the name of the new user and then click on "Invite user and create share".
A welcome mail is then sent to the user and the new user can either register for the service as a user of an authorized institution or as a guest.

Is online editing offered? 
Yes, the possibility of collaborative online editing is offered based on ONLYOFFICE.
Is it possible to merge accounts if I have multiple email addresses?
Merging accounts is not possible on Nextcloud.
Each account has only one email address and no other email addresses can be added to an account. For users who log in via Shibboleth, the email address is transmitted from the IdP of the participating institution to bwIDM and thus to bwSync&Share.
What is new with Nextcloud or different from the Powerfolder software that was used until March 2020?
All files and folders are automatically stored encrypted on the server. This eliminates the need to encrypt individual folders.

The integrated end-to-end encryption in the Nextcloud software used does not work together with the activated server-side encryption.
If you absolutely need end-to-end encryption, there is the Cryptomator software.
Since, in our experience, data loss can occur when using Cryptomator in conjunction with server-side encryption, we cannot recommend using Cryptomator.
If you use Cryptomator, you should back up the data elsewhere to be sure that you do not lose any data.
Invitation: Other users can also be invited to subfolders and files. - Before the changeover, this was only possible for top-level folders.
Accept invitation: Whereas before the conversion, the invitation had to be explicitly accepted, the new default setting provides for shares to be accepted automatically. If you want to change this setting, go to Settings -> Sharing and uncheck "Accept user and group shares by default" under Sharing.
Visibility of users: Users who have been invited to a folder or file will only see the other users who have also been invited to this item if they have permission to share the folder or file itself with other users (Share allowed).
Transferring elements: When a folder or file is transferred to another user, the new user does not receive an e-mail, but instead a new notification is displayed on the Web page for that user and the user must agree to the transfer.
After the transfer, the folder or file files will be displayed in a subdirectory called "transferred from ..." for this user. (Before the changeover, these folders were visible in the top folder level).
The previous owner loses all permissions for this item and must be re-invited if necessary.
Merge accounts: Merging of accounts is not (yet) possible on Nextcloud.
Each account has only one email address and no other email addresses can (yet) be added to an account.
How can I transfer a folder to another user? 

To transfer a folder or file to another user, click the colored circle in the upper right corner with your initial letter or profile picture and click Settings.Then click Share in the drop-down list on the left and click the "Select file or folder to transfer" button.
If you want to transfer a folder, go into that folder and click on "select" without clicking on a single file.
If you want to transfer a file, select the file and then click on "select".

Attention: There will be no automatic e-mail be sent to the user to whom you want to transfer the item. Instead, the user will receive a notification on the website and must agree to the transfer.
It may take a few minutes to transfer the folder.
After the successful transfer, you will receive a corresponding notification on the website.
You will lose all permissions on the item when you transfer it and must be invited to the folder again if you want to continue to have access to the folder or file.

How can I restore deleted files?
After deleting files, these files are moved to the "deleted files" folder (= trash bin) of the owner of the data.
If a person with whom the data was shared deletes these files, the files will also be moved to the "deleted files" folder of this person.
All other people with whom this data was shared will no longer have access to these files.
To recover a deleted file, click on "deleted files" in the bottom left corner of the web browser and select the file(s) to be recovered by checking the box. Then click "Actions" at the top of the page, and then click "Restore".
How can I access my data via WebDAV?
If you try to log in to Nextcloud via a 3rd party client, you will encounter the problem that the 3rd party client probably can't handle Shibboleth. The solution is a so called App Password. You can set this password in the settings of your account under "Security" at the bottom.
Local administrators and bwSupportPortal
What are group administrators?
There is a separate group in bwSync&Share for all universities and colleges that participate in the bwSync&Share service.
This group contains all users who log in to bwSync&Share via the institution's identity provider.
Group administrators can be named for each of these groups, who can view all members of this group and change the storage space for individual users.
The group administrators can be named by the authorized persons and then receive the corresponding authorizations from the operator of the service.
What permissions do group administrators have in Nextcloud?

After logging in, group administrators will see the "Users" item on the service website if they click on the colored circle with their initial letters in the top right-hand corner. If you select this item, you will see a list of all users who belong to your institution's group.

On this page you can make the following changes for these user accounts:
- Change the storage space size (the "quota") of individual users.
- Deactivate users
- Deleting user accounts and their data

How can I, as the local administrator of my group, view and change the storage space of a user?

To see the storage space of the users in the group for which you are entered as group admin, after logging in to bwSync&Share, click on the colored circle with your initial letter in the top right corner and click on "Users" in the menu that then appears.
This will give you a list of all users at your institution.
To change a user's quota, click on the pencil in that user's row in the right margin.
Under "Quota", click in the field that says "Select user quota" and select a value there or enter the desired value including the unit GB, e.g. 100 GB. Then click Enter. The maximum value you can enter is 200 GB.

What is the bwSupport-Portal and how can I register for the bwSupport-Portal as a helpdesk employee of a participating facility?

The bwSupport portal is the interface between the first-level support of the facilities participating in the bwSync&Share service and the operator of the service.

As an employee of the helpdesk of a participating institution (first-level support), you can report problems or requests to the operator of the service via the bwSupport portal that you cannot solve or answer yourself (second-level support).

The login to the bwSupport portal is done via Shibboleth.
To be able to report requests or problems via this portal and assign them directly to the bwSync&Share support unit, you must first register with the bwSupport portal and request access to the portal.
To do this, log in via Shibboleth on the and then click on "Register" under "My data".

Then fill out the registration form and as soon as the authorization has been set by the operators of the bwSupport portal, you will be informed by e-mail. (Prerequisite for the release of the authorization is that you have been designated by your institution as a helpdesk employee for bwSync&Share. If this is not the case, you will be asked by the authorized person of the institution whether the release of the authorization is desired by the institution).

Afterwards you have access to your support group and can create and edit tickets and also see all tickets created by other members of your support group. When creating tickets, please assign them to the support unit bwSync&Share (under Second Level -> bwToos). This way you ensure that the ticket ends up with the responsible persons right away.

On the page you will also find a link with further instructions on how to use the bwSupport portal.

Emerging problems
The same name appears several times when sharing after entering an email address.

In this case there are 2 accounts in bwSync&Share that are connected to the same email address. In this case, please contact the helpdesk at your institution so that they can open a ticket for second-level support via the bwSupportPortal. In consultation with the affected user, the unneeded (guest) account will then be deleted.
Only after the deletion of the second account is a clear invitation of the user possible.

The bwSync&Share website is not displayed correctly.

In case of initial errors in connection with calling up, please delete the cache/temporary data of your browser used.
Check whether the use works properly afterwards.

How can it happen that the "Share" function is not displayed?

If the "Share" tab in the Nextcloud web interface has disappeared, this may be due to an ad blocker. In this case, it would help if you deactivate it and reload the page. A caching error is also possible. In this case, clear the cache and reload the page.
What to do if you find that the client does not synchronize?

Please take a screenshot of the error message and send it to the first level support of your institution with the request to send this screenshot together with the error message to the second level support.

What to do if your account is locked?

From experience, it may happen that users who use an iOS client are disabled.
This problem has been forwarded to the Nextcloud company, but we need log files from affected users so that the Nextcloud company can fix this error.
Therefore, please send the iOS log files, which you can find under "more" -> "settings" -> "advanced" -> "show log file", to the first-level support of your institution with the request to forward these log files to the second-level support.
We will then reactivate your account so that you can log in again and use the bwSync&Share service again.

There is no logout button

We are working on making this function available to you in the future.

When editing Office files via web interface in OnlyOffice at the same time as making changes to the file via client, the synchronization may result in different versions of the same file.

So it can happen that the system creates different versions of the same file. These version conflicts must be resolved by the user. If the changes are very close to each other in time, the system cannot distinguish whether the last version was edited online in OnlyOffice or locally. Also, uploading a previously syncronized file that is still open in OnlyOffice can result in overwriting the last changes without warning.
Before editing a document offline, the status of the file should be checked in bwSync&Share and, if necessary, a user should first download the latest version of the file. Simultaneous editing both via client sync and in the OnlyOffice web editor is unfortunately not reliable.

When installing and starting the Windows client (in Autostart), several system error messages of the type "The execution of the code cannot continue because QT5ml.dll was not found..." are displayed.

This is a known problem and has been fixed by the software manufacturer in client version 3.x.
Please install a newer client if you are experiencing this problem.

There is an error message when accessing bwSync&Share with the Linux desktop environment KDE: "Access prohibited - Your login token is invalid or expired"

A workaround for this can be found at

Some files are constantly uploaded to the server, even if they are not modified

It is possible that another program may change the modification date of the file. If the file uses the .eml extension, Windows automatically and continuously changes this file unless you remove 
\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows \CurrentVersion\PropertySystem\PropertyHandlers
from the Windows registry. You can find further information under

Synchronization stops if an attempt is made to synchronize that is deeper than 100 subdirectories

The client was deliberately limited to the synchronization of no more than 100 subdirectories. This hard limit exists to protect against bugs like symbolic link loops. If a deeply nested directory is excluded from synchronization, it will be listed with other ignored files and directories on the "Not synchronized" tab in the "Activity" area.

There was a warning about changes in synchronized folders that cannot be tracked reliably.
If the synchronized folder contains many subfolders, Linux may not allow enough inotify watches to monitor changes in all of them. In this case, the client cannot immediately start the synchronization process if a file in one of the unmonitored folders changes. Instead, the client displays the warning and manually scans the folders for changes at regular intervals (every two hours by default).
This problem can be solved by setting fs.inotify.max_user_watches sysctl to a higher value.
This can be done temporarily: echo 524288 > /proc/sys/fs/inotify/max_user_watches
or permanently by adjusting /etc/sysctl.conf

If you find that the results of synchronizations are unreliable, please make sure that the folder you synchronize to is not shared with other synchronization applications.

Synchronizing the same directory with Nextcloud and other synchronization software such as Unison, rsync, Microsoft Windows Offline Folders or other cloud services such as Dropbox or Microsoft SkyDrive is not supported and should not be attempted. In the worst case, synchronizing folders or files via Nextcloud and other synchronization software or services may result in data loss.