I also had the same problem. I was able to fix it by following all the above mentioned methodologies.
1. delete all the cookies, tempory files
2. Download trojan remover software and run it.
3. It will identify all the malicious, unwanted and suspisious registries, policies etc. within ur machine
4. Restart the machine.
Note: If you have upgraded versions of IE like (IE 7, IE 8), better to remove them also. After fixing the above issue
you can again install it. :)
This works for me. I have 20 users. Unfortunately, I have to do this once in a while for each of them:
1. Cloose all applications
2. Close / disable startup applications (such as skype, messenger, or any background application)
3. Start/Settings/Control Panel/Internet Options/Delete Browsing History/Delete All (in passwords)
4. Also delete files and settings stored by add-ons (check) and click ok
5. Close all windows, and files, (just in case) nothing has to be open
6. Go to Start/run
7. Type in the open: %temp%
8. Press enter
9. Start deleting the temp files
10. You might not be able to delete some of the files, because ther are in use. Leave them alone.
11. When you get the error: Error Deleting file or folder click ok and continue deleting some of the files by type
12. When you are done. Reboot the computer
13. try accessing your companyweb or sharepoint site again.
I JUST WANT TO SAY THANK YOU SO MUCH FOR YOUR HELP! THANK YOU TO TROJAN REMOVER! I CAN FINALLY GO TO ANTI-VIRUS' SITES AND MICROSOFT! THANK YOU THANK YOU THANK YOU! MAY GOD TRULY BLESS YOU SO MUCH! THANK YOU! :)