Due to the structure and format of the files that Jobs, Projects & Libraries consist of, some Error 104s and the majority of Error 105s can be fixed via running Check Job & Check Library or by restarting the application. However, error 104 can also be related to something making the files temporarily inaccessible, such as antivirus scans, permission changes, or network installs or connectivity issues.
Before investigating these types of causes, it is best to check the project and library integrity:
From the Tools menu, select Check Job
Preview the report
If it says errors have been fixed, run Check Job again. It shouldn't error twice.
If Check Job preview gives a warning message other than "errors have been fixed", please continue with a support member for further assistance. ConQuest support has other tools they can use to attempt to repair this - they will need .zip files of your project and library, which you can create from the Tools menu under Zip.
If your project has been fixed or shows no errors, repeat the process for checking the library.
This can also be caused by interruptions to the network connection. This is most likely to be the case if you restart ConQuest and have no further errors.
If you are on a Remote Session, try CTRL + ALT + END to sign out and back in again.