I am using visual studio 2015. I have my toolbox open and I checked on Show All. I unchecked this an now my entire toolbox is empty except for the General Tab (which there is nothing in). I tried resetting the toolbox but that did not fix the problem. Has anyone encountered this before? If so, what was the fix? Thanks.
Try right clicking in the toolbox and select 'show all'.
You can also start /reset
From your description, it seems that your issue might be related with IDE. I suggest you to try to execute the following commands:
Devenv.exe /SafeMode
Devenv.exe /ResetSettings