Quick Letters Hanging/Non-responsive for DAYS

While we are moving to NXT later this month I have started having major issues while running Quick Letters for some of our regular selections. While the audience size has been increasing over the last year I have only started having this issue in the last two months. I'll try running a Quick Letters segment with output query without writing the Appeal back on the records or updating the number solicited and the process just hangs for days. The time to run our newsletter has gone from 2-3 hours to 12 and now 36 hours+ (is still running, and showing as non-responsive). I am running directly on the server through a remote desktop and other colleagues and I can run other processes while this ticks along which may slow slightly, but does not explain the length of time while running overnight when nothing else is running. It does not seem to be an issue of space as the server has adequate free space.Our IT department has previously tried rebooting the server to try and free up memory and such but that didn't actually make a difference and just meant that I had restarted the Quick Letters and had to wait 3.5 days for it to run.


Does anyone have any suggestions, or have come across this in the past? Also would you know if this is likely to be solved when we move to NXT?


Thanks in advance for any response, I'm at my wits end and up against the wall on deadlines because of this.