Max locks up opening files

so if I'm working along on a job and I need to open another file I save, go to file open and select my new file. Recently max has started locking up when I open the new file. The work around (which is annoying) is to shut down max, start it back up and open the file. The problem has now spread to xrefs which makes this more problematic because I need to update an xref location but as soon as I do max locks up.

I've tried taking the files off of the network which didn't make a difference. I also check to see if I have any user paths pointing to the network, I don't. A coworker tried to update one of the files I'm struggling with and his machine locked up too. I tried creating a new file and xreffing the model into that. It worked until I hit the "ignore lights" check box (which causes the file to reload).

Any suggestions would be appreciated.

It may or may not be related, but I recently had a project that took about 30 minutes to open. It turned out I had forgotten to collapse a terrain mesh on my gigantic site and it was recalculating a few boolean operations every time I opened the file. Once I figured that out, it opened in seconds.

That's a good tip. I'll have to look through the geometry and see if there are any excessive modifier stacks.