My .bdf file crashes Quartus Prime, can it be recovered ?

Thanks for your reply KhaiY_Intel, but I managed to recover the file. The file was actually about 3/4 finished when somehow it simply ended, I was working remotely via a VPN connection to a shared drive down at the office, so that may have had something to do with it. Using Notepadd++ , I was in the section where the point to point connections are called out, my file ended with ( CONNECTOR (pt xxx yyy) and then nothing else. It should have been (CONNECTOR (pt xxx yyy) (pt xxx yyy)). I simply removed the last unfinished connection , and the file was able to load. There were a number of connections missing in the schematic, but the majority of my work was there. I now also work on the local drive, making backup copies every hour or so to a thumb drive. To answer your question, I was running the Lite version of Quartus Prime 19.1