EDIT: IGNORE THE POST BELOW I AM STILL GETTING A PROBLEM WITH THIS…
I am on Siteground shared hosting and I noticed that their “static cache” was a possible cause to “gateway timeouts” and “magento errors” upon logging into the admin panel for Magento backend.
I disabled it and now this error seems to have disappeared, now if timeouts were produced I might have also solved the “PayPal showing orders but not Magento” error as well.
I would also like to add that their “dynamic cache”, “supercacher” and “CDN cache” all caused different timeouts, errors and issues. So turn all of these off and just use the native cacher with Magento.
With all due respect to Siteground, I don’t see any performance difference with or without all those cache features.
This also explains how some people managed to solve the issue after switching host (maybe one of them had cache features which lead to conflicts with PayPal).
I will keep you updated and let you know if this truly fixed the dreaded “PayPal shows order but not Magento error”.
Any updates on this issue? One of my clients is experiencing this (CE 18.104.22.168) and I am under heavy pressure to resolve it.
I have seen about 5 occurrences of this problem since October 2010. In all cases the credit card payment is approved (via Website Payments Pro) but there is no trace of the order in the Magento admin area.
For a couple of the orders (but not for all of them) I was able to track down the corresponding quote in the database table sales_flat_quote.
I have PayPal debugging switched on, and there seem to be messages going back and forth, but the sequence is not the same on these failed transactions as on the normal ones. Unfortunately I do not know enough about the transactional conversation between Magento & PayPal to be able to interpret the differences…
I had initially thought the missing orders were due to a network/firewall issue preventing the hand-off from PayPal to Magento. But I realized today that at least one of these “interrupted” transactions came from an IP address which had submitted successful orders on other occasions.
So my only viable hypothesis now is that the transaction must be timing out during the hand-off following payment approval. I have not been able to ascertain if the customers saw an error message or not.
What I do know is that I am getting occasional “System Error 500” messages for no apparent reason on the administrative backend, which I have seen on other threads may be due to memory or timeout limitations on 1&1;Shared Hosting.
Can anyone say if they are experiencing this “missing order” issue and/or the “System Error 500” issue on dedicated hosting and/or on hosting other than 1&1;Shared Hosting?
Any other bright ideas out there??