Problem with virus/spyware... HELP

have been working at this for the past 3 days searching various forums trying to disinfect my PC. Here are the issues I've found and what I've done about them to no avail. Any assistance is greatly appreciated. Thanks in advance.

1. Notepad won't open. When I attempt to review a .txt file, I get a data execution prevention message stating it is helping protect me against viruses.

2. My browser has been hijacked. I can open IE7 and navigate to search sites like google or yahoo.com, but whenever I type symantec or trend micro in the url or search field, I get diverted to some type of advertisement.

To resolve this: I have used browser hijack retaliator 4.5. I've tried some of the knowledge base articles on MS website. I modified the registry values as suggested to make sure there was no winsock corruption. Didn't work. I have tried just about everything. Nothing is working to bring it back to normal.

3. I can't run most .exe files downloaded to get rid of the spyware (I cant run HJT either).

To resolve this: I ensured the registry was set up properly to execute the files. I also found this exefile repair utility and that didn't work either. I tried everything in safe mode as well. Nothing

4. I can't update any of the definition files within the antivirus or spyware prevention applications I attempt to run. I have an internet connection but when I click the update buttons within the applications, the error states I should check my internet connection. I have been manually extracting the files and inserting them in the appropriate directories.

I know the computer had a virus because I disabled the NAV and ran the scanning tool that kaspersky has and it found some worms and some hidden objects in registry but that didn't resolve any of the issues mentioned above. I still can't use the browser, i still can't run any exe files, I can't open notepad, etc. Any help or recommendations is greatly appreciated. Thanks.

 

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