When you say "Windows Support" are you talking about the website or your Help and Support utility accessed by clicking start/help and support?
The Windows Malicious Software Removal Tool is not a scanner type anti-malware utility. While good to use, (and have update automatically) you need to be using others too for a layered approach.
To start with, because you are experiencing a percieved problem which can be attributed to a variety of causes, I recommend you run the Windows One Care Free Scan.
Go to Windows Live Onecare Free Scan
It will say "Get a free PC safety scan"http://safety.live.com/site/en-us/default.htm
Make sure you click "Full Service Scan"
in the middle of the page and not the "Try It Now Free" on the right side.
Allow it to download an Active X component.
Choose "Complete Scan" in the window that opens
Do not click on anything else that offers you a free trial or to sign up if you live in the US.
Allow it to scan - it may take quite, maybe two hours or so depending on how big your hard drive is and how fragmented your registry and drive are.
Using the above occasionally is a good start to help keep malware at bay.
In addition to a good, automatically updating Anti-Virus program running in the background the following aps are recommended.
Ad-Aware SE Personal - freeware http://fileforum.betanews.com/detail/Adawa...nal/965718306/1
Update – Aug 2006 - Spybot by default now ignores certain products such as New.Net and Sidestep for no good reason. New.Net compromises the WinSock stack by routing all your DNS queries through the NewDotNet.DLL. To enable detection go to "Settings", "Ignore products", "All products" Tab, right click on "Product", left-click on "Deselect all". http://www.safer-networking.org/en/index.html
Be sure to enable “Teatimer” which gives you realtime protection against malware invasion.
Microsoft Windows Defender
Windows Defender will give you an additional tool in your control panel named Software Explorer which is excellent for examining software installed on your computer, its startup menu, etc which will help you identify what it is.http://www.microsoft.com/athome/security/s...re/default.mspx
This also provides realtime protection.
Ewido Antispyware Freehttp://free.grisoft.com/doc/20/lng/us/tpl/v5
A² - Free from http://www.majorgeeks.com/download4281.html
. Run it, click Search for Updates, then click Scan
Here are some web based scans to use when you feel you may have become infected or as an occasional verification that you have not been:
Kaspersky Anti-Virus Web Scannerhttp://www.kaspersky.com/service?chapter=161739400#betatest
File scanner and virus scannerhttp://www.kaspersky.com/scanforvirus
Trend Micro antivirus and malware scan:http://housecall-beta.trendmicro.com/en/st...orp.asp?id=scan
Etrust Anti-virus web scannerhttp://www3.ca.com/securityadvisor/virusinfo/scan.aspx
Avast Online scanhttp://onlinescan.avast.com/
F Secure online scanhttp://support.f-secure.com/ols/start.html
Ewido Online scanhttp://www.ewido.net/en/onlinescan/
Trojan scans –
Windows Security Trojanscanhttp://windowsecurity.com/trojanscan
See instructions for it here:http://www.windowsecurity.com/trojanscan/trojanscan.asp
Parasite scan from Aumha:http://www.aumha.org/a/noads.php