I've been sorting out my MP3s this weekened and this is driving me nuts ! Getting the following error sporadically in Windows Explorer: If I wait a few minutes, it frees up the file or folder and allows me to move or or delete it. It doesn't happen all the time, say every five attempts. This makes me think it's a thumbnail caching problem, as eventually whatever is causing the problem is released by itself, so it seems unlikely to be a third party program. All the solutions I've seen relate to disabling thumbail caching use the local group policy editor (gpedit.msc), but I have Home Premium and this feature is disabled in it. Been Googling all afternoon and found nothing. Anyone else had this and resolved it? I will have your babies if you help me sort it.