I can help by pointing you in the right direction about how to upgrade your company file without any error messages standing in the way. To fix this problem, you'll need to reset the admin password on the 2014 version first and then try to upgrade it afterward. Here's how:
Go to the Company menu.
Hover over Set up users and passwords.
Select Change your password.
Make sure Admin is already in the "User Name" box and then type in the new password.
Try running the verify and rebuild tool. If the error still persists, call and ask Intuit Data Service to fix it as mentioned by ShiellaGraceA. Should you need to resolve it in due course, consider purchasing a 3rd party file recovery service.