How to Fix Proof.Cab Errors on CDs

By Todd Bowerman

If you are attempting to install Microsoft Office and some variation of the error "Cannot Find Proofing.en-us" occurs, you may be experiencing a common symptom of drive confusion. This occurs when the installer tries to locate a necessary component of the software but looks in the wrong place. You can fix this error and successfully install Office with a quick edit to the installer.

Step 1

Open the Windows search function by pressing the "Windows" key and the "F" key on your keyboard simultaneously.

Step 2

Type "proof.msi" (without quotes) into the search field and press "Enter." You may need to use the "Advanced Search" option to search everywhere instead of the traditional indexed locations.

Step 3

Write down the location of the file once it has been located. The path should look something like this: C:\MSOCache\All Users\{90120000-002C-0409-0000-0000000FF1CE}-C\Proof.en

Step 4

Run the Microsoft Office installation wizard again. When the error appears, go to the input field at the bottom of the error message and remove the "proofing.en-us\proof.en\proof.msi" from the file location using the "Backspace" key.

Step 5

Type the file location that you wrote down in Step 3 into the box at the bottom of the error message (this is the input field that you cleared in the preceding step). Press "Enter" to complete the installation.