Tried adding an item, but when I clicked to add, it sent me to admin_product.php which was a blank white page.
 
To troubleshoot, I added the item again and did one page at a time. General, Stock, etc, and clicked to add each time then went to Edit to add the next page. Finally I tried adding to the Description page and that's when it happened. I wondered if there was anything in my text that would have caused this, so I tried entering one word then updating, then another word and updating, and so on. It accepted it to a point, then I got the white page admin_product.php again. There wasn't anything in the text to cause a problem, it was just normal alphabet characters.
 
This happened on one item today and one item yesterday.
 
I uploaded fresh files to the admin folder, but it didn't help. I checked the error log, but no errors were generated.
 
Has anyone else had this problem?

I'd like to add that it's also doing this when updating stock on some items now as well.