Orders not posting to database
I am using PS 4.50 and PayPal payments standard. PS has been working well for me the last couple of years but for the last 5 days not a single order has posted to the database (roughly 10 orders) and no order receipts are being sent out. The orders still process through PayPal and other functionality seems in tact, i.e. customers can register, get their passwords, etc.
I checked PayPal's ipn history for these orders and they all show as having been sent and having received an HTTP response code of 200 which from PayPal's documentation I think means my store successfully received them. My technical knowledge isn't strong so I might be mis-reading this.
The IPN page in PayPal matches the notification URL showing in power store and looks like this.
Notification URL https://mystore.com:443/webassist/plugins/shopping_cart/ipn.php
Any ideas what might be going wrong with my store?