Thanks For opening this thread
The story is that there is Four computer Using XP OS Service Pack 2 in workgroup connected in Lan network.
and there is a folder in one of these four shared for all of them
tow other computer can connect to the share folder but  third of them cant
before he COULD Access to share folder but now it is not accessing to the share folder.
the computer that is not accessing to share folder can access to other tow computers
and the computer that contains the share folder also can access the error given computer.
i tried much but i couldnt solve this pro
Note: Dont forget that the computer which is giving the error can access to share folder if i enter as a administrator i mean that if i log on as a administrator on that pc that pc can access to share folder but the other user cant. the user also have administrative privileges.
the error given pc has the Mcafee anti virus but the other three dosent have.
i thought that the mcafee is creating problem but the amazing is that when i logged on as an administrator it accessed to share folder but as a user it couldnt
i dont know ther user also have administrative privileges
Waiting for the solution.Update them to SP3, and any other Critical Updates that are on Windows/Microsoft Update.

Try that first, there are some important fixes in SP3, one MIGHT be for that.

It probably WON'T be the solution, but at least we'll know for certain, and it's ALWAYS better to be fully updated anyway.
It's just a GOOD place to start.i have updated them to SP3  but the problem is the same
can u send some troubleshoots about this PROBLEM

I sure can, it just helps that you are now updated as well. 

Go into the computer that is hosting the share, and take a LOOK at it's privelages, if you want limited accounts to access the share you must declare that.