External Reference File Has Changed... or so it says

Working with a drawing where I've attached some XREFs and I've got this one (out of about 8 or 9) that is constantly giving me the balloon pop up that it has changed and needs to be reloaded. I open the XREF manager and I reload it, but the yellow triangle remains with a "needs reloading" message. No one else even knows that the XREF'd file exists, and it hasn't been modified by anyone (myself included).

What gives? Does anyone have a solution to this perpetual need for reloading?

Is this xref saved on a server? if so someone could be messin about with it, or is it saved to your harddrive?

It's on a server but no one has touched the file. There are only two computers that have access to it and I'm the only one who has used it.

I've had this problem a few times myself and from playing around I found that if you detach and save the drawing, then re-attach the xref the balloon notification will no longer pop up unless the xref has been saved.

This is just what I've found out to work. There may be a setting somewhere to keep this from happening but I'm not sure.

just a shot in the dark but do you have the xref'd drawing open when you are working on the other drawing that references it and you have a timed autosave set for your drawings that are opened? Maybe the autosave refreshes it in your xref'd drawing?