I SSH Hotfix – Hotfix Authorize.net for Direct Signature After Signing – PATCH_SUPEE-11085_CE_126.96.36.199_v1-2019-02-28-05-21-55.sh and he was successful following the instructions provided here – https: / / support .magento.com / hc / en-us / articles / 360024368392? flash_digest = f47655cd8c97b1c9a32f9f6a6cf0a05174642823
I entered my security key and registered it successfully. I then made a purchase and when I select "Place an order" at the end, all that happens is that the page is flashing. I do not receive any error. I do not know what's wrong. I contacted Authorize.net and they said to contact Magento.
Authorize.net Direct Post transaction key update (MD5 to SHA-512)