Just recently a new version of the Minecraft launcher was released. I dutifully installed it, simply to get rid of the annoying message nagging me to update it. Imagine my shock when I started up the new version and discovered that my rather extensive list of installations was now almost completely empty!

A quick browse around my computer reassured me that the files were still there, just that the launcher had seemingly forgotten they existed. The most likely reason for this is a configuration file being overwritten. At this stage there was a 50-50 chance I could recover my installations, so got to digging around.

A quick glance in the .minecraft folder didn’t show any obvious candidates for the file that changed, so I had to do more research. I jumped on my other laptop and made a backup of the .minecraft folder and updated the launcher. After the update I had the same issue, none of my existing installations existed any more. Fortunately, I could now compare the backup to the new version and find what changed.

Fortunately the cause of the problem was easy to find. The old launcher used the file launcher_profiles.json to store information about the installations. In the new version this file is called launcher_profiles_microsoft_store.json.

The updated config files

In a perfect world it would be possible to rename the old file to the new name and have everything work, right? Well, this ain’t a perfect world, and that didn’t work. So, I opened the files up in a text editor, and looked at how they were set up. There were a few differences, but it was nice to see that the information about the actual installations seemed to be identical. Could I fix this by copying and pasting the sections for the installations between files?

Turns out, yes, you can do this, and it fixed my issue beautifully. Here’s how to do it:

  1. Open the launcher_profiles.json file, and look for the second line with “profiles” : {
    The line below this is the start of the installation information
  2. At the bottom of the file look for the line with “SelectedUser”, the end of the installation information is two lines above this.
  3. Copy everything between these two sections
  4. Open launcher_profiles_microsoft_store.json
  5. There will be the line “profiles : {” as with the old version of the file
  6. Paste everything you copied from the old file below this line
  7. When you open the Minecraft launcher all your old installations should show up.