**As** an administrator responsible for storages
**I want to** get a warning when a Nextcloud storage has pre-existing folders that could prevent project folders to be created automatically
**so that** I can delete the blocking folders from Nextcloud

**Acceptance criteria**

* When the user clicks "Recheck connection" the OpenProject folder on Nextcloud will be analysed for unexpected Begin of the insertionfolders.End of the insertion Begin of the deletion folders. End of the deletion

* If unexpected content is found, return a warning to the user: Begin of the insertion WRN\_UNEXPECTED\_CONTENTEnd of the insertion Begin of the deletion  WRN\_UNEXPECTED\_CONTENTEnd of the deletion

* The validation test only applies for storages that have AMPF enabled. Storages without AMPF skip this validation test.

* Begin of the insertion~~TheEnd of the insertion Begin of the deletion TheEnd of the deletion warning links to the description in the documentation Begin of the insertion(https://www.openproject.org/docs/system-admin-guide/files/external-file-storages/health-status/#connection-validation-for-nextcloud)~~End of the insertion Begin of the deletion (https://www.openproject.org/docs/system-admin-guide/files/external-file-storages/health-status/#connection-validation-for-nextcloud)End of the deletion

* The warning is documented in the linked table of the documentation Begin of the insertion

* If the group folder cannot be found at the remote storage, return an error to the user: ERR\_GROUP\_FOLDER\_NOT\_FOUND

* If the app password is badly configured, retun an error to the user: ERR\_USERLESS\_ACCESS\_DENIED

* This can happen, if an nextcloud admin resets the already configured app password on their sideEnd of the insertion