Sorry to hear you are unable to access your company file. Can you provide a little more information please - how do you launch Reckon Accounts and open your file, at what exact stage did the error appear and what is the full message?
If you launch Reckon Accounts from C:\Program Files (x86)\Intuit\Reckon Accounts 2017\QBW32EnterpriseNNNN.exe does Reckon Accounts open? Then open your company file - do you get the same error? do you have any problems opening the sample file?