Explorer.exe opens after a reboot when the 1st program is started. It takes 25% of cpu and takes about 1 minute to complete the action. This I can accept, but after this, explorer does the exact same thing whenever any program is run. The attached screenshots show that ntdll.dll!AtlAllocateHeap+0x18c seems to be the culprit. I have reinstalled winxp sp3 to no avail. I'm just totally stumped. Help please.