I've started getting warnings that my start up disk is nearly full, but I've not really added a great deal and last time I looked I had over 120GB free. I have a 1TB SSD and just checked both user accounts and they equate to roughly 680GB used, so where's the rest of my storage gone? I appreciate the OS uses some, but not 330GB I've emptied both trashes (Have 2 user accounts) and now have 21GB free. I've just used Omnidisk sweeper and here's the results, showing 680GB used. Here's a screenshot of my hard drive usage, which shows that it still has 1TB capacity so it's not lost storage capacity. Any help/advice appreciated.