how can i remove the internet explorer "certificate error" from my internet

Easy, switch to Firefox.

It sounds like spyware but follow these instructions carefully and if the problem is not corrected then you call microsoft. at 1-800-936-5700
Good luck.

HOW TO DO A THOROUGH CLEAN UP:
Before doing any of the maintenance steps outlined below make sure that your system is free from viruses and/or of any other undesirable Internet bugs, by running a thorough security scan of your machine.
Now, do the following as needed:
“I” (FOR WINDOWS XP-IE6)
While you are connected to the Internet do the following:
1. Click on tools ... Internet options. There you will see three buttons next to each other... “Delete Cookies” ... “Delete Files” and “Settings.” Also, below the settings button you will see another one “Clear history.”
2. Click on “settings” - go to “Edit” - Click on “select all” - Go to files, click delete and wait till all Internet trash files are gone.
3. Go back and click on “delete cookies” and wait till all cookies are gone
4. Go back and click on “Delete files,” put a check mark on the little white square shown on the small window that will open, click OK and wait for a little.
5. Go back and click on “Clear history”, click “yes” and you are done. Go to item “III” now.
ADDITIONAL INFO.: Here is how to clean website addresses from you IE6 browser bar: While you are connected to Internet, go to “Tools” … “Internet Options,” “Content” tab … “Auto Complete button” … click on “clear forms” and you are finished.

“II” (FOR WINDOWS XP-IE7):
Go to Start … Control Panel … Internet Options. Under “Browsing history” click “Delete” and then click “Delete all,” put a check mark in the little white square and then click “Yes” and you are done. Go to Item “III” now.

“III” (FOR BOTH WIN-IE6 AND WIN-IE7)
1. Do a check disk and a defrag, then restart your computer and see if the problem is resolved. It is assumed that you know how to do a check disc and disc difragmentation.
2. If the above steps don’t do the job, here is a little program that keeps your machine in shape and free from Windows micro-problems that lead to slowness and crashes:
Get on the web and go to http://www.tune-up.com/products/tuneup-utilities/site; download the free trial program, familiarize your self with it and use it to clean up your registry automatically along with a sort of other helpful and useful maintenance chores. It is an excellent little program and does wonders with PC maintenance tasks and I strongly recommend it! It works on the background on its own automatically.
3. After you are through with the above maintenance steps, go to Microsoft/Windows updates and download any and all available and/or applicable updates.
Hope this helps!
NDS