Closing "TOAD error" window closes TOAD application without prompt

Hello,
I have a problem, very irritating.
When “TOAD error” window appears and i’m closing this window, TOAD dissapears …
I have to run TOAD again and as a result I lose all not saved queries and statements.
No mater whether I click OK or Close button, the behavior is identical.

My operating system is XP Pro SP3, and TOAD version is 9.7.2.5

Can anyone help me?