Can my problem be a virus?

Edit Note: Please don't post the same information multiple times. Things get too confusing. I merged two others into a single thread Here. Newt

Well, I have been having this problem for a couple of days now. First, Everything was fine in my computer (I was running both norton antivirus and firewall 2003). The problem came when I installed microsoft's service pack 2. After the install, I started having trouble running both norton firewall and the windows security center at the same time. So I decided to take norton firewall off of the startup list. After this, the windows security center warned me that the position of my virus protection was unknown. So, I disabled norton anti-virus for a couple of days (a virus could have entered my computer at this time and maybe that is what is causing the problem).

Then, I thought that the windows security center (windows service pack 2) could do everything to secure my computer, so i tried to unistall both norton firewall and norton anti-virus. (before trying to uninstall both programs, i tried running them and nither of them worked. Norton firewall 2003 professional said the following message:Symantec integrator error # 0xE06D7363).
When i tried to unistall the firewall and the anti-virus, there was another problem. An error message appeared when i pressed the remove button in the add or remove programs. After this error message, i got frustrated, so i manually erased any file that had or was in a folder with "symantec or norton ". (i erased them using safe mode, because otherwise it wouldn't let me erase the symantec "shared components ").

After erasing all the files for the virus protection and firewall, i unistalled the service pack 2. Now, i cant install the service pack 2. When i go to the microsoft update website an error message appears saying: Windows Update has encountered an error and cannot display the requested page. Error number: 0x8007043C.

And this is where i am now. I am not running any antivirus or firewall. I have repeatedly tried to install the norton firewall... but it gives me this error message: The microsoft windows installer may be corrupted or your system may be infected with a virus. I tried contacting both symantec and microsoft for support, but they both charge for any kind of help. ( I used up my 2 free support calls for microsoft). Now i don't know what to do... if there is someone out there that could help, please let me know. I could give you more specific details about my problem. I would really appreciate any help you could give me.

 

Up to date...

ok, so no virus programs, or firewalls... if it is a virus what can i do?