Check these entries in regedit:
for VS2013
HKEY_CURRENT_USER\SOFTWARE\Microsoft\VisualStudio\12.0_Config\ToolboxControlsInstaller
for VS2015
HKEY_CURRENT_USER\SOFTWARE\Microsoft\VisualStudio\14.0_Config\ToolboxControlsInstaller
They should contain the Wisej toolbox entries. If the 14.0_Config is missing it means that the installer didn’t add the items for VS2015 (maybe the VS2015 checkbox wasn’t checked). In this case you can rerun the installer and select Repair.
If the entry is present, you can right click on the toolbox and select “Reset”. The items will be reinstalled automatically.
HTH
Best,
Luca