Accessing QB 2015 Desktop for Mac file to convert to QBO
So, I updated my Mac to MacOS Big Sur and I can no longer open my QB 2015 application. I would like to convert this file to QBO, but I cannot open/access it to "Export to Quickbooks Online". QB 2015 simply isn't supported any longer and won't even open.
Do I have to buy the latest Desktop version to access and update this file before converting to online or is there a way to access this file and convert it without doing so?