I am getting Memory address couldn't be written error message frequently. Most of the times it occurs on opening Internet Explorer. Some times "Buffer Overrun detected" error message is displayed.
Please tell me how can I get rid of it.
I am using Windows XP SP2 and internet Explorer 6. McAfee antivirus is installed.

Buffer overruns are usually caused by either malware or a corrupt program. Both are trying to write more than the buffer will allow - so it overflows the buffer.

This is a technique used by malware to gain control of your system - so I'd first suggest running a couple of these free, online scans:

Be advised that some of these scanners will pickup things in "quarantine" from other anti-virus programs - so review the results carefully:

http://housecall.trendmicro.com
http://www.pandasecurity.com/homeusers/solutions/activescan/
http://www.kaspersky.com/virusscanner
http://www.bitdefender.com/scan8/ie.html
http://support.f-secure.com/enu/home/ols.shtml
http://us.mcafee.com/root/mfs/default.asp
http://onlinescan.avast.com/
http://ca.com/us/securityadvisor/virusinfo/scan.aspx
http://www.eset.com/onlinescan/

<links compiled on 02/14/2008>

Problem couldn't be resolved after scanning with couple of spywares.
McAfee find a lot f files of Vundo virus, but these files are not deleted permanently by McAfee. When I restart my computer and scan again those files are found.
Is above memory problem occuring because of Vundo virus?

Problem has been resolved. It was occuring because of Vundo virus.
Thank You