If the Project Import fails, it will often leave you with an inaccessible project. Trying to import again will advise you that this cannot be done because the project is in an inconsistent state (that files exist or do not exist already).
To correct this, you will need to move or rename the folder for the problem project.
To locate the project, highlight the project in the project register - The location is given at the top of the right-hand panel.
Navigate to this location in File Explorer
Move or rename the project folder.
If you are not confident about moving or renaming folders, either get your IT to do this.
Before attempting to import again, check that you do not have your Project Totals set to "update on every change" as this will often cause the import to fail:
Go to Options
Scroll to the bottom of the first displayed panel
Check that Project Totals is either turned off or set to update only on a refresh.
You should now be able to import the project, however, it may take some time. This is especially true if you are working across a VPN (which is not recommended), so if you or one of your colleagues can do the import from a machine which is on the same network as the server, that would be more likely to work.
Important: DO NOT click anything or fiddle with ConQuest in any way while it is importing, this makes it a lot more likely to fail. Just let it complete. If it hasn't thrown up an error message, it just needs more time.