Backup failed, unknown error

[DaMi]

Hi Folks,
I'm facing serious problems about 2 of my veeam backups of virtual machines. The report says:

Backing up VM files RunPolicy failed Client error: ERROR: HookEnd command received Cannot write a data chunk to a cyclic buffer. Chunk size: [262144]. Cannot push data chunk to the VCB backup stream. Chunk size: [262144]. ERROR: in drv cycle: Server error: Incorrect function Failed to write data to the file [D:\path\file.vbk]. Unable to process VCB backup commands.

I couldn't find any hints about this error message. The backup terminates at 7.7GB of 385GB. After rebooting the backup server it runs until 160GB of 385GB before terminating with error.
Any suggestions?

Thanks in advance!
DaMi

[Alexey D.]

Helo DaMi,

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