I just recently upgraded my DNN installation to 8.0.3. After the upgrade I received a 500 Internal Server issue which was related to the conversion of a Icon Path being converted to an Int for some reason. After solving that issue I felt like things were good, however after further inspection I have many issues still to address. 

1) When I try to add a new Module to a page the list of modules never loads. It just spins. The same issue occurs when trying to add an existing module to a page with the list of Pages not loading.

2) When I access the DAM module on the File Manage tab a popup comes up that says that Folder Content Not found.

3) Attempting to upload a file fails.

There doesn't seem to be any errors associated to these issues in the Activity Log.

Normally, with this many issues I would just revert back to my previous version. However the guy who manages the server did a snapshot of my DNN Installation Server but not the DB server, so I was stuck trying to solve issue by issue. Any help would be appreciated.

Running .Net 4.6