Matlab Report Generator errors occasionally when closing the document, why?

I am using the Matlab Report Generator to build and save a PDF report. When I clsoe the report and below messages haapen. Do someone know what happen?

Error using mlreportgen.internal.fop.createFOPObject

Failed to create file modification time character vector.

Error in mlreportgen.internal.fop.createFOPObject

Error in mlreportgen.internal.fop.createFOPObject

Error in mlreportgen.internal.fop.foToPDF

Error in mlreportgen.report.ReportBase/close

Error in

close(MeasReport);