Port 5900 Blocked
Running a screen sharing app on my iMac that uses port 5900. It worked fine until recently. Now I have to turn off Norton Security Firewall Connection Blocking to make it work. Spent time with Norton support chat yesterday and after trying several methods to allow port 5900 remote access he ended up completely blocking all remote access (except for his remote access program that took over my machine) to my iMac. His solution was then to download and run a terminal program that removed all of the norton files on the computer followed by reinstalling Norton Security. Fixed the problem for all of about ten minutes (during which time all I did was check to see if the port was accessible remotely) before the problem returned. Using canyouseeme.org and checking for port 5900. Works fine with Connection Blocking turned off as does the remote screen sharing app. Both fail with connection blocking turned on.