Comment 2 for bug 1048045

Thank you for report.

To track down the error, could you start pdfchain from a console window (terminal), please?
When you then concatenate pdf files, the used pdftk command
should be displayed in the terminal.

Do you get an error message when you run this command by hand?
Or does pdfchain display any error messages in the console?

Are spaces or other special characters in the path or
filename of the input (or output) pdf files?

Another reason for the bug could be a wrongly set PATH environment variable.
So run "echo $PATH" in a terminal and send me the result. Of course, you can replace
any private information by random letters.

In certain circumstances, it could be helpful if you provide scanned pdf files which shows this strange result,
but as it looks at the moment, the problem is outside pdftk.