Gmail will not Compose from my computer? But, it will compose mail from other comps?

Cannot Compose mail with Gmail on my computer- ROOTKIT?
I cannot send any mail with GMAIL on my computer, this just happened a few days ago. I can send gmail from any other computer, but it will not send from my computer. If I click "compose mail", it just says "loading" and never finishes loading. Could there be a rootkit virus on my computer? I ran a full kaspersky scan after updating and no viruses were found. I also ran a rootkit remover from kaspersky: http://support.kaspersky.com/viruses/solutions?qid=208280684

That also did not find any rootkits on my computer. So what could be the reason for this problem in gmail? Do I need to try a different rootkit scanner?
I have done full scans with malwarebytes and superantispyware and nothing was found.
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The problem:
unable to send email with GMAIL from my computer


Details of problem:

-upon clicking "compose mail", gmail just says "loading" and never stops "loading", nothing happens with it. I cannot send nor reply to email with gmail on this computer.

Relevant INFO:

-This problem is only for one computer, other computers in the house do not have this problem
-Just recently happened a few days ago
-I have a fast internet connection
-I have not added any addons
-I am using mozilla firefox, however, the same problem occurs with opera
-This just happened suddenly, no new software was installed. No hardware was added.
-Interestingly, yesterday, I was not able to access mail.yahoo.com or google.com from this same computer; the browser gave some type of error, i forgot what it said, but now that problem just went away, it lasted for maybe 12 hours.

I have gotten a hijackthis.log and found several items stating "unknown owner" and "file missing". These files seem to be important windows files, for example, here is are some lines pasted below:
O23 - Service: @%systemroot%\system32\spoolsv.exe,-1 (Spooler) - Unknown owner - C:\Windows\System32\spoolsv.exe (file missing)
O23 - Service: @%SystemRoot%\system32\Wat\WatUX.exe,-601 (WatAdminSvc) - Unknown owner - C:\Windows\system32\Wat\WatAdminSvc.exe (file missing)

Should I paste the entire hijackthis log? Any ideas why I cannot send mail with Gmail from my computer?

Thanks!

 

Re: Gmail will not Compose from my computer? But, it will compose mail from other com

You may be correct about that. But, what else would cause this problem? I have uninstalled firefox and reinstalled but that did not help. I also do not have any firefox add ons or extensions that would be causing this.

 

Re: Gmail will not Compose from my computer? But, it will compose mail from other com

I have tried Internet explorer- Gmail is working with internet explorer. I just tried with opera, and its also working with opera now. But it still will not send mail with the firefox browser.

 

Re: Gmail will not Compose from my computer? But, it will compose mail from other com

Yes, firefox is now working with gmail. I did what you said.

Thanks!