CAD+ Toolset misbehaves if 3rd party add-in is enabled. Alternatively 3rd party add-in may misbehave if CAD+ Toolset is enabled.
Add-ins developed in the .NET (C# and VB.NET) loaded in SOLIDWORKS will share the same application domain. In some cases this may result in the conflict between loaded libraries.
Go to the installation folder of CAD+ Toolset and run the RegCadPlusSwAddInConflictFixer.cmd as Administrator. Types registered successfully message is displayed. Restart SOLIDWORKS
To remove the fix: go to the installation folder of CAD+ Toolset and run the UnRegCadPlusSwAddInConflictFixer.cmd as Administrator. Types un-registered successfully message is displayed. Restart SOLIDWORKS