License file corrupt
A -7089 error indicates that the library was attempting to read information from the license file, and was unable to find important, required information. Also, the library will not read from a license file if the file fails to pass one of several built in security checks. For more specific information and a cause, we generally need a logfile collected as the problem occurs with LogLevel set to 4.
While is is impossible to determine the exact cause of the error, even with a logfile, the most common cause of a -7089 error is for something outside the library to move the local license file (the *.lic file in the WorkDir), then later copy it back into place. This sort of copying is often an attempt to by-pass usage restrictions, and so it is detected and prevented by the library. Depending on how it operates, backup software or a network file system may trigger the same error.
Solution
If a machine (virtual or physical) is powered down or crashes while the library happens to be writing to the license, the license can become corrupt. To safely shutdown the library you must call NalpLibClose(), and wait for the function to complete. Check also that the license file is stored on a persistent file system, and is not being moved or copied.
Unless you are using consumption tokens, it is always safe to delete the license file, and let the library re-create the file during app startup when the license is refreshed with a call to NSLGetLicense() or NSLObtainLicense(). If there were remaining consumption tokens, the license file can still be deleted, but the remaining tokens will be lost.