“The system administrator has set policies to prevent this installation”

Source
------xp, server 2003, Vista------
Worked like a charm on Win2k3 and VMware Server 2 installation problem:
Solution:
Fix the local security policy.

1. Open control Panel and go to Administrative Tools.
2. In Administrative tools open Local Security Policy.
3. In Local Security Policy right click Software Restriction Policies and click “New Software Rectriction Policy”.
4. Now Left click on software restriction policies and in the right-hand window you should see enforcement.
5. Double-click on enforcement and set the policy to apply to “ALL USERS EXCEPT LOCAL ADMINISTRATORS”

Now approve the changes and see if you are now able to install software.
Alternately several people recommended the following but I’ve found the above steps fix the problem in 98% of cases.  If you are unfamiliar with the registry…. stop reading.

1. Browse the registry to HKLM\Software\Policies\Microsoft\Windows\Installer
   Create: DisableMSI       Type: REG_DWORD  value = 0   (0 should allow you to install it was originally 1)
2. Browse to HKEY_CLASSES_ROOT\Installer\Products\
   Search the list for the product that is causing the error.. delete the folder in the products folder…  this may also correct your error…

If you have any additional comments or pointers they are welcome.
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***** UPDATE ******
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I’ve gotten alot of comments that they cannot find secpol.msc.
This is because it is not included on Home versions of vista.
However, I now believe I have an answer even to this.  I have spent the last hour reviewing the registry changes that are made and have narrowed down the value that is changed when you set the above policy.  The Value changed is a dword value :
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Group Policy Objects\{A541BD3D-1A70-4D7B-BC99-CF1ADFC0DE9F}Machine\Software\Policies\Microsoft\Windows\Safer\CodeIdentifiers\PolicyScope
It is changed from 0 to 1 when you set it not to apply to administrators.  When you set “new software restriction policy the following tree is populated:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Group Policy Objects\{A541BD3D-1A70-4D7B-BC99-CF1ADFC0DE9F}Machine\Software\Policies\Microsoft\Windows\Safer
I am not sure if you need the whole tree to get it to function or just the value I have included 2 Registry files to run.   The first includes just the policyscope value of 1 the second includes the entire “Safer” tree that was created on my machine when I added the software restriction settings.
Click here to download just the PolicyScope setting.  (download and run first to see if it fixes your problem.)
Click here to download the entire “Safer” tree that manually adds the fixed software restriction settings. (try this if the above reg file does not fix your problem.)
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Vista Home Premium 32 bit
I turned my User Account Control off here:
Start>Control Panel>User Accounts>Turn User Account Control on or off
Vista 64

Try turning off UAC
Control Panel>User Accounts, User Accounts,
Turn User Account Control on or off
http://forums.techguy.org/windows-vista-7/657215-system-administrator-has-set-policies.html
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The solution provided here worked for me…
http://social.answers.microsoft.com/Forums/en-US/vistasecurity/thread/84890be5-45c2-4e4d-af2f-37e72fbfe3b1
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this is what finally worked
http://msdn.microsoft.com/en-us/library/aa367561(VS.85).aspx
I created the AlwaysInstallElevated under local user since it did not exist and turned set both to a value of 1. Create a restore point prior to messing with the Registry and using REGEDIT.
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