JSON formatting error

Hi,
Downloaded the trial to see if this is for me.
Created a database and used the generator.
Uploaded the whole and ran the file.
Getting the result:

DataTables warning (table id = 'tabletest1'): DataTables warning: JSON data from server could not be parsed. This is caused by a JSON formatting error.

I don't have time to spent hours searching for the solution so mayby someone could point me instantly to it.

Thanks a bundle
JohN