PME8.1 ：Trend shows "Updates Paused"

Trending Updates Paused will happen if there are communications issues with the device, or the server is down, i.e. ION Real Time Data service is not running. If you click on the 'i' icon (it's in the read box in the screen cap) you will see the log file which will give detailed information as to what has failed.
If you see the 'i' icon at all, there has been some problem, likely communications related, but not enough to put Trends into a Paused state. The Trend will go into a Pause state if there it fails 3 times to get a real time update in a 2-3 minute period.