CGJQPDFViewer help needed

I am tryng to use the CGJQPDFViewer to view a PDF file from the Cache folder.

I am copying the file to the Cache and setting the  

I get the error in the PDF viewer :

Message: Missing PDF "http://127.0.0.1:8888/$/MyApp/zHOG5EAdJuoVjqQJqQUg9W/EXP_20170525_583001.pdf?cache=1731781782136".

The file acually does exist in the temporary cache folder ???? I even test that it exists before I assign the value

s1 := WebApplication.UserCacheDir+ExtractFileName(UserSession.qry1DocFile.Value);
s2 := webapplication.UserCacheUrlBase+ExtractFileName(UserSession.qry1DocFile.Value);


  if fileexists( s1)then
      PDFv1.JQPDFViewerOptions.PDFFileName:= s2;