I have migrated data from magento 1.9 to magento 2.2.4, Now in admin when i view shipment under sales -> Shipments it gives me 404 error. How am i suppose to debug? I have checked the .phtml file from where the form is displayed on view but it is not reaching over there. when is go to sales -> Order -> edit -> shipments in left panel it is working fine when i view shipment Any help would be appreciated
It looks like a routing issue, forwarding action to the other controller doesn't work as expected.
Can you try changing the below file around line 49
$resultForward->setController('order_shipment') ->setModule('adminhtml') // Change admin to adminhtml
This seems to be a known issue that is fixed and the fix will come with 2.3.*
See here https://github.com/magento/magento2/issues/12206 for the full thread and possible patches.