How to recover "state.xml"?

Hi
Suddenly, we weren't able to use a Pipeline Pilot user. We recognized that at the same time an error occurred "Pilot Error: CXMLReaderFunctions::ReadXMLFromFile(Object): failed reading state.xml: Pipeline Pilot exception rethrown". So we looked into state.xml and there is a huge part missing. How can we recover the state.xml file and save the user and its protocols?
Kind regards,
Lina