"Error 1303. Setup cannot access the folder C:\Program Files\Common Files\Microsoft Shared\Web Folders\1033. Verify that the folder exists in your system and that you have sufficient permissions to update it."
The first solution was to try and change permissions on the 1033 folder. That was unsuccessful and gave an "Access Denied". But I was able to get a solution that worked.
OS: Windows 7
Problem: Office 2010
Solution: I was logged in as a user that was added to the local Administrators group, but that wasn't good enough. You must enable the local administrator account and turn off UAC. To turn off UAC -> Control Panel -> User Accounts and Family Security -> User Accounts -> Change User Account Control Settings -> Drag the bar to the bottom and then select ok. You will then be required to reboot for it to apply. Link
To enable the administrator account -> Click Start Or Use My Computer Desktop Icon -> Right click My Computer -> Manage -> Local Users and Groups -> Users -> Right Click Administrator -> Uncheck "Account is Disabled"
From there... Navigate to C:\Program Files\Common Files\Microsoft Shared\Web Folders\1033. Right click the folder and select Properties. Select the Security Tab and click Advanced. Click the Owner tab, enter your username in their to take ownership of the folder. Click apply and you should now be able to access the folder.