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Article ID: 2756166 - Last Review: April 21, 2014 - Revision: 8.0


When you try to download and install Office 365 Home or an Office 2013 suite, you may receive the following error message:

"We're sorry, but we can't verify the signature of files required to install your Office product."

To fix this error, try the following methods.

Method 1: Try a wired connection

If you're using a wireless connection, try connecting your computer through a network cable instead. This may also speed up the download and install process.

Method 2: Clear temporary Internet files

To clear temporary Internet files on Internet Explorer automatically, run this Fix it:

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Fix this problem (
Microsoft Fix it 50472
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If you can't run the Fix it, and you use Internet Explorer on Windows 7, follow these manual steps:
  1. Click Start, and then go to Control Panel.
  2. Open Internet Options.
  3. In the General tab, click Delete under Browsing history.
  4. Select the Temporary Internet files check box.
  5. Select the Preserve Favorites website data check box if you don't want to delete cookies and files associated with websites in your Favorites list.
  6. Click Delete.
To clear temporary Internet files in Windows 8, follow the instructions in the “To delete browsing history” section of Reset Internet Explorer settings ( .

If you still get the error, change the download file name. To do this, use the following method.

How to change download file name

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  1. Follow the same steps you took initially to start the install of Office.
  2. When you see the option to Run, Save or Cancel click the drop-down arrow next to Save and choose Save As.
  3. Look at the filename in the Save As dialog box. If it contains a number in brackets like this [1] at the end of the filename, remove it.
  4. Save the file, and then go to the location you saved it to.
  5. Open the file to start the install.
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More information

For more information about deleting temporary internet files and webpage history, go to this Windows article: Delete webpage history ( .
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