A friend of mine bought an Arisaka Type 99 rifle over the weekend, the bolt is froze shut. I thought maybe the safety was on and thats why it would not budge, but he said he turned the safety both ways and still the bolt is froze shut. Can this be rusted shut? Or is there something else that's obvious?
Thank you for your help.
I would bet on the safety being in the wrong position. You need to compare it(the position of the safety) to one that is functioning properly.

The safeties on those (IIRC) were a bear to manipulate, even when the rifle was working the way it was supposed to. I haven't touched one in 15 years or so, but I recall that the best way was using the heel of your palm. You have to press like you really mean it–– ten pounds of pressure or more if memory serves. More than you'd reasonably expect of a properly functioning rifle, it seems like.
The bolt also had a tendency to catch on mine.