I'm struggling with one issue which I think started about month ago after last firmware upgrade. Earlier, everything was ok.
What is the issue:
My QNAP ( TS-251, 4.3.5.0713 ) is added to domain.
On the device we have one share with assigned AD users who can have access there ( via SMB and also via File Station )
About month ago I started getting information from people that they can't see one network drive ( above share ) and additionally when they are logging into QNAP via https and trying entry to File Station, they can see only: "You are not QSync user".
Additionally I have some extra shares where scheduled backup is copying via Veeam from our servers. It also stopped working.
Error from Veeam: Access is denied, Error code: 0x00000005 ( Veeam is setup to use domain account to access dedicated share )
I think that somehow QNAP is loosing trust with a domain because when I will re-add it again to the AD, everything is starting to work but only for 1-2h and again ... same issue. What is strange, user can't login to the QNAP using their DOMAIN\user account ... but as above, Filestation is not working.
I can't see any errors in the notification center. I also didn't change any kind of settings into QNAP. It has been working continuously for 2 years ...
Time is setup properly and DNS included IP address of local DNS server.
I'm loosing my hear with this. I'm kindly ask you for your help.
Please let me know if you need any additional information from my side.
Waiting for your feedback.
Thank you in advance