Question: I'd like to run a pptp vpn server on a raspberry pi in my home network behind a fritz.box.

It should work like this:

Android - internet - fritz - raspberry-pptp - internet

Client can connect, but no internet access.

1723 and GRE are open on fritz and should go to raspberry.

How do I have to iptable to make Android get internet via raspberry?

Answer: 
Question

> 
> ***Pie fired - Why?***
> 
> 
> 

***Answer***

There is 50% chance that the pins 1, 2, 3 labelled below are hardwired to Gnd or Vcc. These pins are used for dry run, without Rpi connected. You use a jumper to short the pair of pins to check out if the motor can move.

But if you connect your Rpi GPIO pins to these dry run test pins, ***Pi fried instantly***.

You might use a multimeter to measure the voltages at these pins, or give me the link to the motor driver to check out the schematics to confirm.

[![motor driver](https://i.stack.imgur.com/myIOG.jpg)](https://i.stack.imgur.com/myIOG.jpg)

[![motor driver 2](https://i.stack.imgur.com/qwSlN.jpg)](https://i.stack.imgur.com/qwSlN.jpg)
I can't see anything obviously wrong with the schematic.

Likely causes.

* connecting more than 3V3 to a GPIO
* connecting more than 3V3 to a 3V3 pin
* connecting more than 5V to a 5V pin