TurboTax does not actually do any save itself, it only call the built in Mac save to do that. This sounds like a local problem on your Mac. I can only suggest a restart (that will destroy any information not saved) or consult with Apple support.
Did you try saving to your desktop?
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
