I have loaded Windows 7 on my primary workstation with XP SP3 in a dual-boot configuration. My user name"mikebo" exists on each of these OS installations but, of course, the Windows7 "mikebo" has a different SID than the Windows XP "mikebo". Therefore, any time I'm working in Windows7 and want to use a file owned by the WinXP-mikebo SID, I get a "insufficient permission" error, and vice versa. When I view the "Owner" of those files, of course, I don't see "mikebo", I see the long SID string assigned to "mikebo" by the other OS instance (WinXP).I have several disk drives on this system, with hundreds of thousands of files owned by WinXP-mikebo. So, I need a way to add WinXP-mikebo's SID to Win7-mikebo's read/write permissions and vice-versa, or MAPthe SIDsin such as way so that the ownership is consistent across the different Windows Operating Systems. I cannot believe I'm the only one with this issue so, I'm hoping there is a better solution than "seizing" the file ownershipback-and-forth, depending on which OS I decide to use.... right? Can someone please offer some advice?In the UNIX universe, thiswould beas simple as editing the user file (/etc/passwd) and modifying Win7-mikebo's UID (SID) so that it matches WinXP-mikebo's. Then I could simply change the ownership of Win7-mikebo's file to match using the change owner (chown) command.I hope there is some workaround that is this simple...Many thanks!mikebo-mikebo

Hi mikebo-mikeboHopefully you've solved your problem by now - I came across your query when searching for an answer to the same issue (this came to a head when I was trying to migrate my mail app across). The quickest solution I came across was this:http://support.microsoft.com/?kbid=308421 (How to take ownership of a file or a folder in Windows XP).This allows you to reverse the procedure.cuckoo22