The system has new security safeguards that the IRS implemented in conjunction with its 13 tax software providers. That follows an embarrassing breach that resulted in the theft of data from 100,000 taxpayers, which the IRS blamed on Russians hackers.

Customers can still file returns, since they're first sent to companies like Intuit, H&R Block and other members of the Free File alliance via free software. However, the glitch has blocked providers from sending the returns to government since yesterday. Filing has been open since January 19th, so if you've already submitted your return, the crash shouldn't affect you.