Having multiple user accounts doesn't affect utilization of system resources, including RAM, unless multiple users are logged in at the same time. During login it may take a few nanoseconds longer to go through the list until your username is found, but nothing noticeable. Over time a system does tend to slow down, though, as a consequence of use...accumulation of installed programs, startup tasks, increased hard drive fragmentation, etc. That's why it's good to perform regular maintenance, such as checking msconfig for unnecessary programs, defragmenting, and clearing out junk files with the likes of CCleaner.
John
May be the wrong forum to ask this, but since I'm running Vista thought I'd ask here.
Does the number of User accounts created on the computer cause any serious problems with memory use, or resources, if only one user is logged on? Also do more accounts slow up boot time?
I have one computer on the network running XP, with 3 user accounts, and it seems to have slowed down a bit, but don't know if this might be a reason.

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