Even when running only one program, I noticed minimal available memory. (Have 512). Observed in the processes (task manager) that some apllication files seem to be duplicates of eachother, albeit in different paths, and all are running!  Did a search for *.exe and found two and three copies of same application file in (for example) Windows\System 32, and in Windows\Service Pack Files, and in Windows\Software Distribution\Downloads. There are 1,947 application files and one large group of them seem to have been created on the same day.  I think i must have created this mess, but now i'm afraid to delete the dupes, and if i do, which ones do i delete? I'm new at these technical issues.  Thanks for any help!