After you update Lightroom 5.4 on Windows, the error "Assertion failed" occurs when you start Lightroom.
Ensure that the My Pictures virtual folder points to the Pictures folder under your user account folder by doing the following:
- Open Windows Explorer.
- Go to C:\Users\[your user name]\.
- Check for the folder named Pictures.
- If you don't see the folder, create a folder named Pictures under folder C:\Users\[your user name]\.
- Restart Lightroom. If the error recurs, restart your computer, then retry. If the error recurs, continue to the next step.
- Click the Windows Start button.
- Type "regedit" in the Search program and files field, and press the Enter key.
- Back up your registry by choosing File > Export. Give the backup copy of the registry a name and location you can remember.
- Navigate to the registry key: [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer \User Shell Folders]
- Look at the value for the My Pictures entry. The Windows default is: %USERPROFILE%\Pictures, which is the Pictures folder under C:\Users\[your user name]. If another folder is listed, check Windows Explorer for that folder. If it does not exist, you have two options. (1) Create the folder with that name in the location indicated in the registry entry. (2) If the Pictures folder exists under your user name folder, double-click the My Pictures entry, and reset the value to: %USERPROFILE%\Pictures
- Quit the registry editor.
- Log off from your account and back on, or restart your computer, then restart Lightroom 5.4.
In Windows, a virtual folder called My Pictures represents the physical folder called Pictures that exists under your user account folder. Clicking My Pictures in your sidebar, for example, takes you to the Pictures folder under your user account folder: C:\Users\[your user name]\.
When the virtual My Pictures folder points to the physical Pictures folder that no longer exists, this error can occur. This error can be caused when the Pictures folder is no longer under your user account folder. It can also occur when the Windows registry no longer points to the appropriate Pictures folder.
The steps in this TechNote solve the issue in either case.