Hi guys,

Recently I've launched a new drupal commerce webshop to sell giftcards, which was previously built using D6 + Ubercart.

I'm currently experiencing checkout problems with some authenticated customers, who aren't able to reach the checkout review page, and the only lead I have is a very brief error "Connection reset by peer" in my apache logs.

Server setup:

Apache 2.4.7 + PHP 7.0 FPM (apache mpm event mode)

Drupal setup:

Drupal 7.44 + Commerce 7.x-1.13

I'm using a one page checkout process which contains:

- Cart totals
- Account info
- Shipping info
- Billing info
- A custom field group containing Order entity fields using Commerce Checkout Field Group module
- Shipping info
- Payment info

Upon submission of this checkout page, a customer is taken to the review page, but some authed customers can't reach it in 99% of the cases. (because I have been able to checkout sporadically using Masquerade on my local setup)

I'm at my wits end and am now turning into free / paid commerce support as I can't resolve the problem myself wihout any more information.

Does someone have a clue, or had a similar issue?

Feel free to contact me for more specific info about used rules etc.

Thanks in advance,

Kim