I'm using 2CheckOut as third party payment provider. I tried ordering couple of times through my own shop for testing and the payment went through successful in the 2Checkout payment page but order failed when it came back to Shopify.
Error Message: "Your payment can’t be processed for technical reasons. Try again or use a different payment method."
The payment is successful at the 2CheckOut side though.
I had both INS Secret Word and Buy Link Secret Word (I've seen you also mentioned "New", mine only says Buy Link Secret Word in 2checkout) set and generated to be exactly the same yet I added this to my shopify (notable b4 I had my 2checkout account activated) and I still got the damn error. This is very serious, I've already spent one whole month with 2checkout back and forth emails to activate my account and now that that is finally done I get this error, that I can't have on my website. Plus two lesser issues that I didn't knew were there, namely the fact that 2checkout requires me to have Telephone Field input mandatory on checkout (dropping conversion rates) and now also realizing it has no integration with my website checkout (it getting redirected to 2checkout, yet again, conversion drops).
At least if I could fix that game-breaking issue, but don't exactly understand what you guys did. I copied that Secret Word again on Shopify but can't try again, not until I get a clear idea of how to solve this, as the above I though I did from the begging, if I'm not misunderstanding anything.
I got the solution, The technical document says to update only INS Secret
word in Shopify. But you must make both INS Secret word and New BUY LINK
Secret word as Same in 2checkout and then update that back in shopify. In
this way, the transaction will work. Good luck.!
This was done, but the error still remained. But then the last steps from Shopify 2checkout settings page helped solve the problem:
0. In 2checkout control panel Access the Integrations → Webhooks & API section in your cPanel
7. In the Redirect URL section, check Enable return after sale
8. For the Redirect URL section leave blank, Shopify will provide the return url.
9. For Return method, select Header redirect
10. Click on Save settings