I have attached a corrupt dummy project with this email to help you recover the project from the .nvb file. Please follow the steps below to recover your data from NVB file:
1. Download and unzip attached file(based on your NVivo version) to your computer.
2. Open NVivo, click on Open Other Project, then browse and select the dummy file saved in step 1.
3. You will be presented with an option to recover from a project recovery file. Select your .nvb file from the list to recover the project. If your project does not appear in the list, you can try searching your computer for any .nvb files, these are project recovery files.
4. The project should open once recovery is complete.
I hope this helps.
NV12CorruptProject (for restoring project backups).nvp.zip
NV11CorruptProject(for restoring project backups).nvp.zip