Below is the sequence of events:

1. User takes any PRINTING option on the menu
(even if it spools report to the file only).
2. It prints successfully
3. User takes any menu option.
4. System crashes: 'Can not write to drive C:'. Fatal exception
error. Blue screen. Reboot.

System works perfectly well for handreds of users. It persistently happens only with some of users.
If somebody saw anything like that, please help.
Thank you so much!!!
Boris Lifschutz