LT not associating with file types

[Anonymous]

I have spent a lot of time on this today and thought I would come to the forum for advice. It appears that AutoDesk have broken the install of AutoCAD LT 2016 with respect to file associations.

We are running Windows 7 and AutoCAD LT 2015 and have decided to upgrade to 2016 due to some of the new features and being on subscription this sounded like a good idea.

After much playing around I have noticed the following:

• AutoCAD LT 2016 plays nicely with file types if AutoCAD LT 2015 is not uninstalled. Once run windows explorer still shows the icons and opens with 2016.
• If AutoCAD LT 2015 is uninstalled or it is installed in a clean environment that is where the problems start. It appears that the installer does not install certain registry values and fails to re-associate or associate files with AutoCAD LT 2016. This means not only are DWGs not launched in 2016 neither are CTB files given a pretty icon etc.
• The registry values noted in this link are not present in a clean install. (See attached image).  The registry values noted in the above link are also not updated by launching 2016 if 2015 is uninstalled and still point to 2015 causing a broken link message to appear.

On the rest of the upgrades we will not be taking off 2015 so that the launcher still works. But on a clean install its still broken on Windows 7. Strangely though on our windows 10 test machine all works fine on a clean install. Go figure.

Any ideas how to resusitate the machines with the AutoCAD 2016 installed on and the AutoCAD 2015 uninstalled? I have tried the uninstall all, delete all trick from this link. The ideas were helpful but none of them worked.

[Anonymous]

PS how do I get line breaks to work? It keeps removing them. Using Firefox.

[pendean · Accepted solution]

Not really: on the same PC with multiple AutoCAd versions installed, Windows defers to the last AutoCAD version run when it comes to many things related to AutoCAD files. It's that simple (and that complicated). If you want LT2016, you start that program. if you want LT2015, you start that program. Avoid relying on Windows Explorer to guess at which program you want.

Do NOT remove and reinstall any LT version over and over again on a single PC, that's just asking for Windows to get messed up big time. I suspect with all that you've done, it may be time to wipe those PCs clean, reinstall WIn7 and start over. Remember Win7 requires SP1 and all updates before you reinstall AutoCAD/LT.

FWIW never remove an older version of AutoCAD until you are positive the new version os wkring fine and you've migrated all that you need from the old one first.

[stevetamplen]

Hello adamkimber2014;

Thank-you for your post, and I am sorry you are experiencing difficulties.

Dean is exactly correct on all counts.

As he mentioned, when you open a .DWG file in a version of AutoCAD, the launcher remembers your last choice and double-clicking any .DWG file after that will open the previously used version. It is always recommended to open files from inside the AutoCAD version you want to use.

Remember, never install an older version over a newer version, since it can overwrite .dll files that are needed by AutoCAD. Always install in order, from oldest to newest. I have AutoCAD 2013, 2014, 2015, 2016, & 2017 happily co-existing on my system.

I am going to mark Dean's post as an Accepted Solution so that other Forum users might benefit.