Could anyone please elaborate on this issue.
Not understanding the point 8 mentioned below link
Point 8 - Send a mail with the attached file which should be printed
Kindly help.
Hi @Monu_Sharma,
Means that you should send an email using your email client (e.g. Gmail) to the address which is set in the configuration.
In the example, the process engine receives emails and start new process instances. The process doesn’t work if you start the instance by yourself.
Please follow the example 
Best regards,
Philipp
Hi Philipp,
Even I am the getting the same error as shown in the screenshot shared by Monu_Sharma above:
"Unknown property used in expression: ${mail.getAttachments().isEmpty()}. Cause: Cannot resolve identifier ‘mail’ "
Could you please help troubleshooting this error.
Regards,
Denny