If you're referring to the alerts the Firefox gives you when a new update is released, then open Firefox, click on "Tools" in the upper left, choose "Options", then select the "Advanced" tab. Once there, select the "Update" tab, and place a dot/tick in the "Never check for updates" option, then click on OK.
Or if you're referring to the CNET Download Watch Alerts, click on the link below, visit your profile's management page in the link listed, change your preferences so you aren't tracking any items, THEN unsubscribe if you need to.
http://www.cnet.com/8739-1_1.html?assetType=watchlist&ursRegId=21190070934194942045750912432709
On the other hand, if you're referring to an alert that is sent to you from this website or Download.com, first make sure you don't have any of the "Update Checker", "CNET Tech Tracker" or the "Download Now App" software installed on your computer. Look in the Control Panel-Programs and Features section and uninstall if it's there.
Hope this helps.
Grif
I have been trying to unsubscribe from one of the alerts I get -- Mozilla Firefox update -- but the alerts continue to come. I click on the "Unsubscribe" link in the email alert, but I don't know what I am doing wrong??

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