'The installer encountered errors before iTunes could be configured.
Errors occurred during installation. Your system has not been modified.
Please run the installer again, or click Finish to exit'.
Quite clearly, a technical problem occurred during the installation of iTunes and the process could not be completed. Without more information, it is impossible to say exactly what caused the problem.
In most cases of this type of error, a complete un-installation of all Apple software before downloading the latest installation package and trying again does the trick. This process includes:
- Un-installing all Apple related components through the 'Add or Remove Programs' utility in the Windows control panel.
- Removing remnants from the 'Program Files' folder and registry.
- Clearing out the temporary folders.
- Restarting the computer and reinstalling.
On this particular occasion, this procedure didn't work. The installation of iTunes rolled back time and time again and resulted in the error above.
Using the logging facilities built into the Windows installer, I was able to identify the problem was with the installation of one of the iTunes components, Apple Mobile Device. Essentially, a device driver for USB connectivity to Apple hardware was failing to install.
I then tried installing the 'Apple Mobile Device' module on its own. Using Winrar, it is possible to extract the iTunesSetup.exe file and install each part separately. The following YouTube video was very useful for this:
Unfortunately this did not work either and the 'Apple Mobile Device' module could not be installed separately either.
Eventually I was able to trace the problem to a single registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\DIFx\DriverStore
On the particular machine I was working on, accessing this key simply resulted in an error. It seems the permission settings for this key had become corrupt.
I was able to resolve the problem by performing these steps:
- Right clicking on the 'DriverStore' key, then clicking 'Permissions'.
- Clicking on 'Add', then typing in 'SYSTEM' in the new panel that appeared before clicking 'OK'.
- Clicking on the 'SYSTEM' object I had just added, then ticking the 'Full Control' box and clicking 'OK'.
After rebooting the system I was able to reinstall iTunes successfully.
I would be interested to hear if anyone else has had the same problem and if they were able to resolve it.