We have MSP360 backup running on a Windows Server 2019. The service is set to backup on 20 minute intervals with another full backup at 11pm at night. Each backup task errors out with a VSS error. The latest error we got was:
Event id: 12289 - Volume Shadow Copy Service error: Unexpected error DeviceIoControl(\\?\Volume{dc5af23e-f187-42b0-851c-b2faaf5c0548} - 00000000000002DC,0x0053c008,00000259285BD1B0,0,00000259285C3210,4096,[0]). hr = 0x80070299, The requested operation could not be completed due to a file system limitation
This is the only windows server that we have this issue on. We have days that it works as intended but then it stops working until we reboot the system, which we can't afford to do every day.
We have contacted Dell, and Microsoft, both of which suggested that we refer to the application support to troubleshoot. We have tried through tickets and were able to fix the issue temporarily but it always returns. We also have had the same issue when backing up through Synology Active Backup. That was without any other backup service running and we still got VSS errors.
The boot drive is on a SSD, and our data is on a RAID. Unsure what defragmentation would do for a RAID since they manage data differently. I can look into it and give it a go but would this solve the shadow copy errors we experience?
I do not know if it will solve your particular issue, and I am only suggesting solutions based on other public posts regarding the same error. That particular error is not logged in our system, but it's possible Support has seen it before. I would recommend you open a support case with them so they can review logs and diagnose 1-on-1 with you. If you are not comfortable trying any of the proposed solutions in the posts, then I would defer to your judgement and wait for some guidance from a support engineer.