ESRI ArcGIS Desktop 10.3 stopped working today giving the following error message: Problem connecting to license manager Provide your license server administrator with the following information: error code = -158

[JohnLang1]

[JayantaPoddar]

Please get in touch with Esri Support to resolve this issue.

[JayantaPoddar]

Meanwhile take a look at How To: Clear or delete trusted storage for concurrent-use and single-use licenses.

You might need to deauthorize all the licenses before clearing the trusted storage. After clearing the trusted storage, you could authorize the licenses again.