Why does my remote access keep toggling off?

Every time someone tries to access my shared server, it shows server offline. I go on my computer, and it seems that the root of the problem is Remote Access keeps disabling it.

I have 1Gb internet through Fios. Bridge connect from Fios router to Apple Time Capsule, and the server runs through an iMac that does not go to sleep. Only display shuts off.

Any help will be greatly appreciated

Mine did that tonight but I am pretty sure it was still on. (no remote users complained)
The icon was red until i click apply then it went green…

My main server is on a big Qnap NAS!!