Why would it do this? Surely this is not
normal behaviour?? I’ve also noticed it doing the same thing when I select my
entire design and delete the tracks. Im new to orcad pcb editor so its highly
possible its just me doing something weird.
in fact, the .dsn file is deleted during the routing of the board. so i no no longer have a schematic!
I can see this occurring if the OrCAD Schematic and the Allegro database reside in the same directory with the same file prefix. When you run the router it writes a .DSN file of the Allegro database which could overwrite the OrCAD Schematic .DSN due to it being the same prefix.
If you did have the Allegro Database in the same directory as the OrCAD Schematic that's what may of happened.
Hope this helps,Mike Catrambone