Problem : restart by itself and config back to default

I have twice experience with mikrotik which restart by it self and the whole config is back to default without any error shown in my syslog. Once with routerboard and another with disk-on-module. Can someone tell me why this happen to my box? is it bug issue or anything else ?

thank’s God that i have backup file inside, so i just load the last backup file i made and it back to normal..

Which RouterBOARD model is used ?

it’s RB532 .. it happened about a few month ago with 2.9.40 version
and with pentium 4 machine just happened a few days ago.. with 1 Gigs RAM with 2.9.43 version

Check that jumper is not closed for RB532 at JP1, if not then check users who are managing this router. Pentium PC should not be reseted only in case someone has used ‘system reset-configuration’ command.

How does RouterO/S respond to a bad block in the filesystem that happens to be within the config file? Does it perhaps delete the config because it’s unusable? Does it run a chkdsk on the filesystem at mount time that might delete the config file because the FAT is damaged?