"Invalid drive X:\" install errors

Symptoms

While upgrading or uninstalling a Windows software package (such as iTunes for Windows or QuickTime for Windows), you may receive the following error message:

Invalid Drive X:\

... where the red X:\ could be any drive letter (F, H, J, or so on.) Usually you won't actually have a drive with that particular drive letter on your system.

Typically, this is caused by a problem with an installer database entry for a component for the software package. The installer database believes that the component is on the X:\ drive. When your Windows Installer goes to remove that component from the X:\ drive while uninstalling the existing version of the software and doesn't find any drive there at all it gets horribly confused and you get the "Invalid Drive" message.

If that is what is afoot with your "Invalid Drive X:\" message, there are a couple of possible resolutions for the problem: (a) temporarily adding an X:\ hard drive to your system, or (b) clearing the installation database for the software package for which you're getting the "Invalid Drive X:\" message.

(a) Temporarily add an X:\ hard drive to your system

So long as you actually have an X:\ hard drive on your system, your Windows Installer will typically remain relatively calm during the uninstall of the existing software (even if it can't find the component it was looking for on the drive in question). So one way of getting past an "Invalid drive X:\" message is to temporarily add an X:\ hard drive to your system.

If you don't have a hard drive available, you could try using the SUSBT command at the command prompt.

(1) Launch a command prompt. How you go about doing this depends on which Windows operating system you're running.

If you're running Windows XP, first open your Start menu and click "Run". Type cmd into the "Open:" field and click "OK", as per the following screenshot:

If you're running Windows Vista or Windows 7, open your Start menu and type cmd into the "Start Search" field. Right-click on the "cmd" item that comes up and select "Run as Administrator", as per the following screenshot:

(2) At the Command prompt, type (where the red X: is the drive letter appearing in your "invalid drive" error message):

SUBST X: C:\

... and press the enter key.

This will map X: to C: until the machine is restarted or you enter SUBST X: /D at the command prompt (where the red X: is the drive letter appearing in your "invalid drive" error message). Now you can try uninstalling or upgrading the software again. (If upgrading the software, install the software in the default location, not on the X:\ drive.)

Otherwise, you will need an external hard drive, a thumb drive, an iPod in manual mode, or any other storage device that appears as a hard drive in "My Computer" (on Windows XP) or "Computer" (on Windows Vista or Windows 7).

Connect the drive to your computer. (If you are using an iPod, and iTunes for Windows launches, quit iTunes.) In your Start menu, open "My Computer" (on Windows XP) or "Computer" (on Windows Vista or Windows 7). Check to see what drive letter has been assigned to the drive.

If the drive letter for the drive you added matches the drive letter being given in the "Invalid Drive X:\" message, try uninstalling or upgrading the software again. (If upgrading the software, install the software in the default location, not on the X:\ drive.)

If the drive letter for the drive you added does not match the drive letter being given in the "Invalid Drive X:\" message, try using Disk Management to change the drive letter of the drive you added so that it does match the drive letter being given in the "Invalid Drive X:\" message.

(1) In your Start menu, right-click "My Computer" (on XP) or "Computer" (on Vista or 7), and select "Manage".

(2) In "Computer Management", click "Disk Management".

(3) Right-click the drive you attached to your computer and select "Change Drive Letters and Paths ..."

(4) Click "Change ..."

(5) In the drop-down menu, select the letter that appears in your "Invalid Drive X:\" error message.

(6) Click "OK".

(7) In the dialog box that comes up, click "Yes".

(8) Close "Computer Management".

(9) Try uninstalling or upgrading the software again. (If upgrading the software, install the software in the default location, not on the X:\ drive.)

(b) Clear the installation database for the software package for which you're getting the "Invalid Drive X:\" message

If it isn't feasible to add a drive to your system, you can try clearing the installation database for the software package for which you're getting the "Invalid Drive X:\" message.

Proceed as per the instructions in the "not a valid short file name" and "invalid character" install errors user tip. (Where that tip refers to "the software you're getting the "not a valid short file name" or "invalid character" message for", read the tip as saying "the software package for which you're getting the "Invalid Drive X:\" message.)