Did anything change between the last time you were able to download and now?
And to be clear, are you talking about downloading software from Download.com, or downloading updates using CNET's TechTracker?
I see a possible issue. IOBit. We don't like that in these forums as we all too often see cries for help after users have 'optimised' their systems to non-workable.
Other than that, options are;
1] Check your Firefox add-ons. Is anything preventing Firefox from downloading from Download.com?
2] Firefox in it's Safe Mode. This is a trouble shooting mode where you can attempt to see if the problem is with a corrupt FF installation or elsewhere. How to start Firefox in safe mode;
http://support.mozilla.com/en-US/kb/safe+mode
I hope that helps.
Mark
This problem was pegged as "solved", but it wasn't. A couple of months ago, I had no difficulty downloading programs and updates from C-Net. Now, nothing happens when I attempt to do that. No security bar shows, no "If download doesn't start, click here" choice, as is found on most other websites. I disabled my download accelerator (Download Accelerator Plus), still nothing. I am able to download from alternate websites with no difficulty. I am running Windows XP SP3 and using Mozilla Firefox 3.6.6 as my browser, with standard Windows Firewall, Avira AntiVir and IoBit Security 360. I followed the set procedures recommended, but nothing changed. I did determine that I can download if I use MSIE instead of Firefox, but I prefer the latter.

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