Troubleshooting a This Payment Solution module could not be loaded Error
When viewing the Manage Existing Gateways tab at Configuration > System Settings > Payment Gateways, the you may see the following error message:
This Payment Solution module could not be loaded, most likely because it has been removed. You should deactivate it now.
You have activated a payment gateway module but the system can't find the file containing the corresponding PHP file in the
To continue using the payment solution, upload the missing PHP files to the
/modules/gateways directory on your server. Then, reload the page.
If you don't need the payment solution, deactivate it.
For more information, see Deactivating Gateway Modules.