I asked around, and found that the cause is a combination of the following:
Browsing from the server hosting Central Administration
UAC Enabled on the machine
Opening the browser without elevation
If you are browsing from a Windows Server hosting Central Admin, you also have IE Enhanced Security Configuration (ESC) to deal with as well.
The fix is to either:
Launch Internet Explorer as Administrator (Right-click Internet Explorer, select “Run as Administrator”)
Browse Central Admin, by clicking the SharePoint 2010 Central Administration link in the Start menu. This runs “psconfigui.exe –cmd showcentraladmin” which will force elevation.
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