This problem just recently appeared: I can't get a response from paypal sandbox (IPN).
I use the following code:
import requests
params = {} #all params paypal sent via IPN, empty here for sake of brevity
params['cmd'] = "_notify-validate"
r = requests.post("https://www.sandbox.paypal.com/cgi-bin/webscr", params = params)
This returns an error message saying "Connection reset by peer"
Note that this code was working fine before, and if I use the live site Paypal URL instead of sandbox, then I still get a response instead of a connection error.
Can anyone verify if this is a problem on Paypal's end? None of my code changed, but since yesterday none of my tests using sandbox will work anymore.
It was actually a problem with my Python code. Oddly enough, I had not changed the requests module, but it stopped working with the same code.
Once I changed to sending the IPN variables through 'data' argument, instead of 'params', then I was able to receive a response like normal.
r = requests.post("https://www.sandbox.paypal.com/cgi-bin/webscr", data = params)