Solidworks Link Module User's Guide.pdfP72 Manually Registering the LT Add-ins 1. Open CMD as admin2. goto LT installed directory : C:\Program Files\Optical Research Associates\LigthTools 8.1.03. if 64bit version, regsvr32 LightToolsLink64-8.1.0.dll3. if 32bit version, regsvr32 LightToolsLink-8.1.0.dll