Ive been doing backups for the last year using xcopy in a bat file under Windows 7 RC without problems. I put on Win7 Home Premium and now the copy dies after a few minutes with a denied access message. If I simply drag and drop or edit/copy edit/past the directory it copies without problems. Go figure I found a PDF file I couldnt openaccess denied message, and right clicked it. I clicked share with/specific people and found myself as owner and an account names unknown contact which had read/write privileges. If I clicked on properties/security there was an unidentified account starting with S-1-5-21 etc. I went back and deleted the unknown contact and was able to open the pdf file successfully. Take ownership didnt change the equation. Closing and re-opening the PDF file caused the S-1-5 etc guy to disappear. After a day of messing around I found only PDF files have the problem and resetting all PDF files to eliminate the unknown contact solves the problem and permits the xcopy bat file to run to a successful completion. I used search and *.PDF for all directories, then selected all via shift/select and eliminated the unknown contact permission. Does anyone have any idea whats going on here? How do these funky accounts/permissions get set?