"An error occurred while installing Adobe AIR"

I am running Vista Home Premium SP1, and I keep getting the following error while trying to reinstall Air. After the install, I get a dialog box telling me Air installed successfully. When I click OK, I get a second box telling me: "An error occurred while installing Adobe AIR. Installation may not be allowed by your administrator. Please contact
your administrator."

This error has repeated itself time after time. Air had installed fine a while back, but programs using it began having problems with uprgrades, so I uninstalled them and uninstalled Air, then tried to reinstall Air.

Here's the .airinstall.log file from the last install attempt:

Performing runtime install
UI SWF load is complete
UI initialized
starting user confirmation
Installation type: new
starting elevated install
subinstaller: starting install
subinstaller: Scheduling runtime installation operations
subinstaller: Installed Product GUID: is same:false
subinstaller: Beginning runtime installation
subinstaller: Beginning install
subinstaller: Installing c:\users\me\appdata\local\temp\air7233.tmp\setup.msi
subinstaller: Execution complete; beginning commit phase
subinstaller: Commit complete
subinstaller: install complete
Elevated install completed
subinstaller: begin quitting
Elevated install failed (3001)
runtime install entering error state: [ErrorEvent type="error" bubbles=false cancelable=false eventPhase=2 text="Error #3001" errorID=3001]
begin quitting


Any idea what's wrong?

Thanks