Timed Out Share Connections

I have a power user (my boss!) who complains that his share connections timeout after a few minutes. They don’t disappear, but when saving a document in, say, Word, it reconnects to all the shares just to save into one. The added time is frustratinghim. And since I live to make his life less frustrating, I’d like to solve this for him. Is it a registry issue? Is there a timeout configuration somewhere that can be increased?