Although I typically tell my clients it's okay to update Adobe when they see a notification to do so, I want to issue a caution regarding those updates. There is currently a FAKE update message making the email rounds and folks definitely want to IGNORE and DELETE this warning.
Legitimate update notices show up in the taskbar (you'll see a little message window down in the corner of the screen by the clock). It's OKAY (and advised) to respond to these messages and update your Adobe software.
However, NEVER respond to update notices received via emails. These are almost always scams. And of course, if you're ever in doubt, don't respond to messages asking you to update. Instead, go the software application's website and download the latest version of the software and install it. This will ensure you're always updated and eliminate the risk of getting caught in a scam.
