Calibri not Found - therefore no pdf created... help

%%[ ProductName: Distiller ]%%

Calibri not found, using Courier.

%%[ Error: invalidfont; OffendingCommand: show; ErrorInfo: CharOffsets ß

%%[ Flushing: rest of job (to end-of-file) will be ignored ]%%

%%[ Warning: PostScript error. No PDF file produced. ] %%

Printing from Microsoft Excel and getting the above error message - and no pdf!