^^^ I like that idea. You may find that it comes down to a single track that's causing the problem, in which case recreating the project could be greatly simplified.

The problem persists even if every single track is archived.

I don't know how long you want to fiddle with this particular project file, it sounds fubar. I would start to rebuild.
 
Here is an idea to see if the project has a chance for recovery. Make to make a copy of the project. Easy if you are using per-project folders, just copy the project directory to another name. Delete all tracks and see what happens. If that does not solve the problem, the project is toast.

I ended up making a new project entirely and copying all the data over track by track. Despite having all the same plugins and data, the new project is almost half the size of the old one and seems to have no problems while saving.

pikerman
I just got Sonar X1 Producer and for some reason I don't have guitar soft synth instrument with available patterns to create songs. Is there anyway to download them and insert them into the soft synth tab

You should start a new thread for your own question. This thread is about Kylotans memory allocation problem.
Anyway, there is no guitar soft synth with pattern library in X1 (or X2) I think (?), even though the soft synths do have guitar sounds. You need to play/compose the parts yourself, string by string, pluck by pluck. You can find MIDI files for guitar in the net for free, but pattern samples...I doubt it. They usually need something like Kontakt to be operational, and they're not free.

Looking through the post history, I think Pikerman is an automated spammer, so don't worry about him!

Kylotan
I ended up making a new project entirely and copying all the data over track by track. Despite having all the same plugins and data, the new project is almost half the size of the old one and seems to have no problems while saving.

Projects get corrupted sometimes; not very often fortunately.