Stop Firefox from Scanning your Downloads

 

Whenever you download something off the net, Firefox first downloads it and then shows a “Scanning for viruses” before it makes the file ready to be open. This is often an useless feature, and still ends up not being able to detect the virus on the download. It is better to turn the feature off, rather than to wait for a few valuable seconds before opening your download.

Turning it Off

In Firefox, type about:config as the URL and click on the “I’ll be careful, I promise” button. In the following list that comes, search for browser.download.manager.scanWhenDone. Double click it and set it to false (or right click it and select Toggle). Firefox won’t scan your downloads from now on.

How does Firefox Scan?

Another interesting question would be how Firefox scans your downloads – whether it has its own Anti-Virus definitions like virus programs, or whether it uses an online service to scan the file for viruses.
The answer is neither. Firefox is just a browser and not an AV program. When Firefox tells it is scanning for viruses, what it actually does is call your anti-virus program installed on the computer and make it check for the virus. But since almost all anti viruses have real time protection, the feature is absolutely useless.
In some cases, the “scanning for viruses” also appears on computers without an anti-virus program, in which chase Firefox would be searching for an anti-virus on your computer. So, this makes it a feature thats safe to remove from your Firefox installation.