February 20, 2013

Associating STEP Files in Windows Explorer to Open Into Single Instance of Solid Edge

A while back I posted on how to open 2D AutoCAD .dwg and .dxf files by opening from Windows Explorer into a single instance of Solid Edge.  Recently saw a request for similar functionality but for opening 3D STEP (.step and .stp) files by default from Windows Explorer into Solid Edge.

You could simply use the Control Panel -> Default Programs settings to associate the STEP file types (.step and .stp) with the Solid Edge executable.  Using this method will result in multiple instance of Solid Edge being launched every time you double-click to open a STEP file from Windows Explorer.

Another issue you may find with using the Default Programs settings is that other software applications may already have defined some registry settings for the .step and .stp file extensions that then prevents setting the STEP file extensions from defaulting to opening with Solid Edge (myself and a customer both experienced this issue).

So if you are having issues associating STEP files to open by default into Solid Edge or want STEP files to open into a single instance of Solid Edge then use the following registry entries:











For your convenience I have also provided a registry file that you can download from my new GitHub site.


  1. Hi,

    i have problem, when i open *.dfl file in SOLIDEDGE ST8, it is still opening in new instance, so i have multiple instances opened. How can i turn it to have it all in single instance? For anothers users it working fine - but they are on Windows 7, I have Windows 10 and only there is problem. Many thanks