I don't know if I'm doing something wrong setting up the gateways via plugins after an upgrade, but the page above throws error. I see it if I go there via the menu and also when I saved the UPS gateway configuration.
Value cannot be null or empty.
Parameter name: contentPath
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentException: Value cannot be null or empty.
Parameter name: contentPath

Source Error:


Line 17:
Line 18: @foreach (var item in Model)
Line 19: {
Line 20: <hr />
Line 21: <div class="row">


Source File: C:\inetpub\wwwroot\GPSstore_ac9\Areas\Admin\Views\Shipping\IntegratedCarriers.cshtml Line: 19

When the site was upgraded, there were already 3 gateways and those remained in the ac_ShipGateways table. I installed and configured the plugins and that changed the values in the table. That did add a second Fedex one, since the old one was the one we had for Gold that we had downloaded, I think from Codeplex. I just deleted it and the page doesn't throw any errors now, but it doesn't list anything. The plugins page shows the configure and uninstall buttons for each of the gateways.
I just tried it on a local site that had no previous entries in the table. I installed UPS plugin, went to the Shipping-->Carriers page and it showed UPS with a plus sign.I clicked the plus sign and put in some settings and it now shows that I can edit or remove the plugin.
The sites have the appropriate gateway dlls in the Plugins.Bin folder.
The site where it worked has an InstalledPlugins.xml file in the App_Data folder. The one with three gateways where the admin page shows none doesn't have an InstalledPlugins.xml file. CORRECTION- the site with 3 plugins does have an InstalledPlugins.xml file. It just didn't show up in VS but was in the file system.
Here's a screenshot of the two Plugins/Bin folders.
2020-11-19_6-56-31.png (51kb) downloaded 0 time(s).

Edited by user Thursday, November 19, 2020 6:15:25 AM(UTC)  | Reason: Not specified

Deleting the old FedEx gateway entry from the ac_shipgateways caused the page to come up with no error, but the UPS, USPS, new Fedex gateways that are installed and configured do not show up on the integrated carriers page. On the 9.0.3 site that was also an upgrade, but had no previous integrated carriers, after I installed the UPS gateway, it showed up correctly on the integrated carriers page.
The InstalledPlugins.xml file had no entries in it before I installed the three gateways.
On the problem site, I cannot go to the integrated carriers page and click on one and make any changes because they do not show up there.

The plugin is installed and configured.
2020-11-23_9-29-41.png (133kb) downloaded 0 time(s).