Hello dear friends,
I have Router OS 6.49.2 (stable) with hAP ac^2.
I can perform backups but I can't restore them at all.
I have this error:
"Failed to restore system configuration
action failed (6)"
No errors while creating backups.
Please help me to restore backup I made.

Would export and import be sufficient as well? Are you restoring to the same device?

Yes, the same device where I have performed the backup.
Today I upgraded from 6.49.2 (stable) to 6.49.5 (stable) but the behaviour is still the same.
There is also no difference if I use encryption or don't during backup.

I'll try export and import and will report to you. Thank your for suggestion a workaround.

Thank you, export is OK, but I wasn't able to restore backup ; )

Thank you, export is OK, but I wasn't able to restore backup ; )

I went through this issue several times over the last few months. I then updated RouterOS and it hasn't happened anymore since.
Anyway, I found out that I could restore my backups via WebFig rather than winbox. Strange, but it worked most times.