And you installed Business 2018 not the Home & Business program? Do you have any other .tax2017 files you can try? Both the Business returns and personal returns both end in the same .tax2017.
Here's an idea. Do you still have 2017 installed? Try opening 2017 program and see if you can get your 2017 return to show up in it. Go to FILE - OPEN.
Then save it again with a name and place you can find. Go to File - Save As. Then start a new 2018 return and transfer from the 2017 file.
