Yes I think that's the way ...but how? I have regoular XP-SP2 cd (Home and Pro) without the patch KB923191 (got them before the release of KB923191). So if I don't install KB923191, the bug doesn't occour. If I install the hotfix, the bug usually happens. It happens also if I install Xp-sp3 from setup (obvious, the patch is included in xp-sp3). Well, the only thing I've not still tried is to do a clean install with xp-sp2 cd slipstreamed to xp-sp3 (integration). But I don't think that will work, because at http://support.microsoft.com/kb/917556/en-us the issue is still "to patch" and not fir e.g. "patched with Xp-Sp3" Yes, thank you anyway! There are also other solutions (regsvr32 shgina.dll ecc.), I've tried them all, but doesn't work. The fact is that I'm not the only user of the 3 Pcs, and the other people are very very newbies and they don't know how to do with ctrl+alt+canc and so on... So I prefer to uninstall (or not install) the update, rather than hearing everytime "Hey! this Pc is locked! I cannot type my password!" thank you all for the answers... still waiting for some other solution...