Thunderbird profiles multiple= If you plan to use a SSD or you already use one, you should not put everything on your SSD. I recommend to keep you normal HDD as a 2nd operating system. Luckily, you can create a symlink to use your Thunderbird profiles on multiple hard drives, e.g. your SSD and HDD.

Tip: If you start Thunderbird, and it starts for 1 second and then closes, remove the folder C:\Program Files(x86)\Mozilla Thunderbird and then re-install Thunderbird

First, install Thunderbird on your SSD. Now, we’re going to create a symlinkfrom in the Profiles folder to the old Thunderbird profile on your HDD.

Creating Symlinks

1. Step Open a command prompt

2. StepEnter mklink /J "C:\Users\[username]\AppData\Local\Thunderbird\Profiles\usbi09ax.default" "D:\Users\[username]\AppData\Local\Thunderbird\Profiles\usbi09ax.default"

3. Step Next, go to C:\Users\[username]\AppData\Roaming\Thunderbird and open the profiles.ini file

4. Step Change the Path to your new profile e.g. Path=Profiles/usbi09ax.default

Step 4. is important because Thunderbird will use that path as your default profile. If you keep the old one it won’t work.


  • mklink /J “new path on SSD” “old path on HDD”
  • replace usbi09ax.default with your own profile on your HDD
  • replace [username] with your own username

Need more help with creating symlinks? Read this tutorial or use this free tool to create symlinks via a GUI

If Thunderbird says it’s already open, then close Thunderbird via task manager and double-check the profile names. Else, reinstall Thunderbird