I'm playing with an old PC that will only accept Windows XP. Been awhile since I've installed a XP OS & have run into this problem: I have successfully installed XP with SP3 & got it activated & no problem there: However, when I try to install something like CCleaner, or an older version of MS Office etc, I get this message : "Error:The process cannot access the file because another process has locked a portion of the file" . I must say, I have in the past, installed dozens of Windows OS's & don't ever recall having this kind of situation. Can anyone shed any light on this? Thanks much !!