A pop-up appeared on my desktop today asking, "Do you want the application "netsession_mac" to accept incoming network connections? The options are Deny or Allow. Having received lots of 'spam' emails recently I am wary of clicking anything that I know nothing about. I did risk clicking the ? on the pop-up and from the information given it says, "When another computer tries to connect to an app over the network or internet, OS X displays an alert message." So the pop-up seems valid but I don't know if I should click Deny or Allow. Could someone enlighten me please. I am on OS 10.11.6 using a Mid 2010 iMac.
Roy, the dialogue you're getting is a standard security check by OS X. The default advice is to 'deny' unless you know what the application is and why it wants to talk to the internet. You then need to understand whether it is malware/adware/cr*pware that needs removing.
In this case, it sounds as though it may be Adobe's doing (see link here) so I leave you to classify it ;-) I suggest you stick with 'deny' for a while, if your updates etc continue to work you could then uninstall it (as it's then classified as, um, superfluous-ware); if some Adobe functions stop working then I guess you'll need to allow it.
If your Mac has been running warm and using its fans a lot (I think it was), this could be related. Have a look at Activity Monitor's CPU usage for a process continually running at 100% (all together now: "I'm busy doing nothing, working the whole day long" - sorry, I'm off on hols shortly and demob-happy). That might point you to an uninstall.
Roy Rainford 