"File exists" error when trying to connect smb shares

My Vero4k was running just fine and connected to my QNAP NAS (TS451) SMB shares without problems. Since a few weeks, I have the problem, that I no longer can connect to my SMB shares on the QNAP (can connect from my PC or MAC without problems).

In the Syslog on QNAP, I don’t see an error, in the KODI logs, I see errors like:

2019-10-19 00:26:09.948 T:3941245664 WARNING: Process directory ‘smb://’ does not exist - skipping scan.
2019-10-19 00:26:10.284 T:3941245664 WARNING: Process directory ‘smb://homeserver/movies/’ does not exist - skipping scan.

2019-10-20 22:59:54.377 T:3558806240 ERROR: SMBDirectory->GetDirectory: Unable to open directory : ‘smb://’
unix_err:‘11’ error : ‘File exists’

2019-10-20 22:59:54.377 T:3558806240 ERROR: GetDirectory - Error getting smb://
2019-10-20 22:59:55.926 T:4069937152 ERROR: CGUIMediaWindow::GetDirectory(smb:// failed
2019-10-20 23:00:59.738 T:3863995104 ERROR: EXCEPTION: Non-Existent Control 300
2019-10-20 23:01:30.467 T:4069937152 ERROR: Previous line repeats 1 times.
2019-10-20 23:01:30.467 T:4069937152 NOTICE: Samba is idle. Closing the remaining connections

The network on the Vero4k is up and running - can ping my QNAP NAS (homeserver) without problems.

The QNAP is setup, that it would allow SMB V2 as min version and SMB V3 as highest version.

Logfiles can be found here: https://paste.osmc.tv/sisevisoci

Any ideas what could be wrong?

Well you could play around with the Samba versions on Kodi (Settings - Services - SMB Client - Max Protocol)
Also gerneally it is suggested to use IP addresses instead of Server Names for the shares as that work more reliable.
Lastly if it is a long term setup I suggest to switch from Kodi based SMB access to kernel based mounts (e.g. autofs).

When this happens it is normally a permission issue on the NAS. I would double check that you have allowed guest access to everyone on the shares. If you are using logins that would need to add those to your sources or a passwords.xml file.

Thanks for all the tips and hints. I couldn’t get it to work with Kodi any more - I suspect, that one of the recent QNAP updates is causing the problem.

So I moved away from KODI SMB to mounting network shares using autofs. This works without problems, when I specify the correct credentials.