Pushover is paid service

Considering you have pushover account (even just trial) and you already installed pushover client on you phone/PC:

1 - Go to https://pushover.net/ and connect with email and password
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2 - Once connected you will be able to get the token 1, the user token
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3 - You also need to generate an application token, which is the token 2
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4 - The token 2 generation: image

5 - Save the generate token 1 and token 2 in ESP3D, and set PUSHOVER as notification supplier
[ESP610]type=PUSHOVER T1=xxxxxxxxxxxxxxxxxx T2=yyyyyyyyyyyyyyyyy

6 - type [ESP610] to verify (T1 and T2 won't be displayed)

7 - Try to send message:
[ESP600]Hi there, test from ESP3D