A feature of Firefox is that it calls your Anti Virus program to scan the downloaded files automatically upon completion of the download process. This feature is nice that it adds an additional layer of protection. However, there are times when you want to disable it. I was downloading a huge file from a trusted source. After the downloading was done, Firefox froze while the file was scanned. It took me a while to kill the crashed Firefox process.
There is no option to disable this feature in the Options dialog. You have to use the configuration editor. Here are the steps:
- Enter about:config in the address bar and press Enter key. You might see a warning dialog. Click on I’ll be careful, I promise! to continue.
- Enter scanWhenDone in the Filter box. Notice the the preference name browser.download.manager.scanWhenDone is set to the default value true.
- Double click on the preference and it changes to false.
- Close Firefox. The next time you use Firefox to download files, it won’t scan the files.
Once you have downloaded those files that have problems with scanning, you might want to enable this feature again.