Here is a fun trick for all the Mac sysadmins out there. If you are using Symantec enterprise protection (SEP) and one of your mac clients has a infected file dialogue window pop up that goes on for ever (meaning the client had several hundred infected files), you can try pressing return forever, or you can do it the smart way.
Launch the terminal app and use:
ps aux|grep -i notification*Kill the process ID that is found and you should be all clear.
IE:
my_mac:~ username$ ps aux|grep -i notification*
username 2084 0.0 0.0 2426928 360 s000 R+ 8:37AM 0:00.00 grep -i notification*
username 2078 0.0 0.1 2768112 7408 ?? Ss 8:36AM 0:00.11 /System/Library/CoreServices/UserNotificationCenter.app/Contents/MacOS/UserNotificationCenter
my_mac:~ username$ kill 2078
kill 2078