There are a myriad of possible causes for this sort of crashing. The most obvious one is if you are trying to open and save files in a synchronising folder such as DropBox, OneDrive, or Google Drive. NVivo files should be opened and closed locally and then backed up or copied to the cloud. Synchronising folders try to grab the file while it’s running to sync it and this can cause apps like NVivo to crash. Equally. if you try to immediately reopen a file, you will get the message the file is in use by another application (DropBox trying to sync the file). If you work in the manner suggested above, this problem should be resolved. It is very important to always have a working backup of your project data file.
Let me know if this is the cause and subsequently solves the problem for you. Otherwise, we will investigate further.
I hope this is helpful but do let me know if you have any questions or concerns.
The QDATRAINING Team