Issues with simultaneous access using a vault through SMB Share

Hi Community!

I expirience several issues using the same vault stored on a SMB share (shared between two users in the network) when using Windows Explorer or Microsoft Office.

Windows 10 22H2
SMBv3_NTFS Share with NTFS and Share-Permission set to “Full Control” for both users
Cryptomator 1.9.1
Virtual FS Provider: WebDAV (Local & Network) or WinFSP (Local & Network)

The issue differs a little depend on which virtual FSP is used. Unfortunately none of them do work well for me sharing a vault between multiple users.
For both providers, as other users already discussed here there is no proper filechange notification through windows explorer.
When a user A creates or deletes a files from the same vault, user B has to manually refresh the directory to see the changes.
This is very annoying and raise various errormessages, e.g. when user B tries to open a file that user A already deleted a few minutes before.

When using Microsoft Apps like Microsoft Word or Microsoft Excel, there are scenarios that can cause some sort of file corruption, when accidentally both users tries to work on the same file at the same time.

Behavior using WebDAV as FSP:

  • When User A opens a word document and modifies it, MS Word writes a temporary file (“~$MyDoc”) that contains the name of the user. (WORKS)
  • When User B opens the same word document the user should get warned that the document is in use by User A using that temporary file (DOES NOT WORK for some reason with files in the cryptshare vault)
  • When User A tries to save the document, the original document (“MyDoc.docx”) in the cryptshare vault is gone! THATS A HUGE PROBLEM!
    Cause: Using procmon I see that Word saves changes in a new temporary file (lets say “A.tmp”) and not in the original file (MyDoc) in the first step.
    After that, Word renames the original word file to a different (lets say “B.tmp”) file, and then the new content (A.tmp) will be renamed to the original file (“MyDoc.docx”)
    As soon as Word tries to rename the temporary file to the original one, Procmon shows an “IO DEVICE ERROR” as a result of that “SetRenameInformationEx” Operation:

    (The same happens with different file formats, like *.rtf shown in the screenshot)

I wasnt able to completely solve those issues by switching to WinFSP (on both users) or to a different type (Local instead of network), but it changed the way how things got wrong, and at least the “IO DEVICE ERROR” (procmon) was gone.

  • User B also does not gets notified that the file is already in Use, and therefore User B saves the document that will be then overwriten by User A without knowing it

I haven’t tried “Dokany” so far, but I think this isn’t a suitable solution either, as Dokany isn’t recommended anymore.

I would appreciate If someone could tries to reproduce those issues, so I know I’m not doing something wrong.