100% CPU Usage

Yup, Your microsoft Access ( MSACCESS.EXE ) contains a memory hole, and is corrupt.

This happens for a number of reasons the most common are:

The Microsoft access is damaged
If software is boot leg ( cracked copie ) and contains a trojant virus etc
if a virus hit your computer at some time and yoru antivirus Quantined the file, ( often leaves the file infected usless and prone to crashes )

you need to reinstall this completely, also if it automatically starts you can press windows key, select run, and enter msconfig into the box.
then under startup, untick the microsoft access box, plus any other annoying things that pop up you dont like.

Also when installing did you tick the box which would say something like ( install for this user and all other users)
And when sharing the application have you also given users Read write and executable rights.
Plus how many users have you trying to access this,
if its only a hand full, perhaps installing it on their machines would be better.

  First of all, there are times when certain versions of Access during normal operation will show 100% CPU usage as a normal part of operation.  See:

ACC: Microsoft Access Shows 100% CPU Utilization During Idle Time
http://support.microsoft.com/kb/160819

  You didn't mention which version of Access is running.

   But in your screen snapshot, it doesn't show 100% for Access, just that the CPU has reached 100% usage, which I believe is what you meant in your question.

  That just says the CPU is working hard.  I don't see how one can jump to the conculsion that Access has a memory hole, is corrupt, etc.

  Since it is recent behavior, then most likely it is something that happened recently and a problem you didn't grow into.  I would start by asking and knowing the answers to a lot of questions:

1. Any applications recently added?  For example, one that jumps out is WinZip; there are 5 instances alone of it in your screen shot.  While I doubt that's your problem, is it possible that someone did an update of something without you knowing?

2.  Any patches or SP's applied to the OS?

3.  Are you using a anti-virus scanner and has a full scan been run since the problem started?

4. Are you running a mal-ware scanner and has it been run?

5. Any errors in the event logs?

6.  Have you rebooted to see if the problem goes away?

7.  You said these where remote users; any network changes or problems?

  The above is a good start and will most likely turn up something, but I would not make any changes until you understand the problem.

JimD.