Lightroom completely freezes after clicking export

I have been using lightroom for quite some time now and just a week ago I was able to click export and my photos would be right on my desktop. But now when I click export the box with all the options doesn't pop up anymore and Lightroom just completely goes unresponsive. It will not let me do anything else on lightroom after this point and I am then forced to force quit lightroom. Please help me try to figure out what is going on and how I can fix this