Strange Error message while updating Min Stock / Max Stock under Item Maste

I wanted to update Min Stock / Max Stock information under Item Master Data form (tab Stick Data) and got the following message:

Error Message: SAP Business One 2005 A: SAP Business One.exe - No Disk.

There is no disk in the drive. Please insert a disk into drive D:.

I run SAP B1 SP01 PL08 build 6.80.318

what's wrong?

thanks