WinXP: You Must Be Logged in as an Administrator When Installing This Program

In a new Windows XP installation, I ran into a situation where my system was running really slowly.  To fix that, I tried to install a program called Advanced Windows Care (AWC).  That program had been superseded by Advanced SystemCare, but for some reason (price or performance, I dimly recalled, but I wasn't sure which), I had decided not to take the upgrade.  I was trying to install AWC as part of a new Windows XP installation.  When I tried to install it, I got an error message:

You must be logged in as an administrator when installing this program.

But I was!  I went into Start > Run > control userpasswords2 and observed that my username, Ray Woodcock, was a member of the Administrators group, just like the Administrator itself.  But according to Philip's SpeedGuide, writing on another issue, being in the Administrators group was not the same as being an (or should I say The) Administrator.

I didn't have the option of logging in as Administrator.  When I booted up, my startup screen showed only the Ray Woodcock username.  To add the Administrator on that opening page, Astrahost advised a registry edit at HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\SpecialAccounts\UserList to add a DWORD named Administrator with a value of 1, followed by a restart.  That worked -- I did have an Administrator account to log into now -- but I still got the same error message.  I checked -- I was definitely logged in as Administrator -- but Advanced Windows Care didn't think so. 

I verified that this was not just an AWC issue.  I tried installing another basic utility, known as Bulk Rename Utility, and got the same message:  "You must be logged in as an administrator when installing this program."

I got a clue from Marcin, who said this:

If the [computer] is a member of a domain, then settings applied via Active Directory GPOs will take effect even when [it] is not connected to the network. Is this the case? If so, you would need to make the computer account a member of a workgroup (i.e. remove it from the domain) in order to be able to modify the local password policy.

Pursuing a search along these lines, I heard Dave suggest that I try Control Panel > System > Computer Name > Change > Member of Workgroup.  But that was already how it was set.  While switching between accounts, though, I noticed that the slowness existed only in the Ray Woodcock account, not in the Administrator account.  So I went into the Administrator account, hit Start > Run > control userpasswords2, selected the Ray Woodcock account, and clicked Remove > OK.  The dialog closed.  I went back into it and the Ray Woodcock account was still there.  I did it again.  This time, I got a message saying, "Ray Woodcock will no longer be allowed to use this computer."  Taking that as proof that computers are not yet smart enough to control the world, I clicked Yes.  That didn't solve the problem of not being able to install AWC, but it did solve the problem of having a slow Ray Woodcock account.  I decided to just use the Administrator account for now.  It was still somewhat slow, but at least it was functional.

To install a program that requires the installer to be logged in as Administrator, Richard Harper suggested (for Vista) that you right-click on the program to be installed and click "Run as Administrator."  There was no option in XP, and anyway, I was already running as administrator.  Carpetfresh indicated that the problem also arose in Windows 7, and the suggestions offered in that case seemed to have been things that s/he had already tried.  After reviewing some other discussions that did not seem to be drawing much attention or producing clear solutions, I decided to take the advice of Buckdog05:  it was unsettling to have a new Windows installation be already showing difficult problems, so I decided to start over.

I tried a repair installation (insert the Windows installation CD, proceed toward installation, but then choose repair rather than a fresh installation).  This seemed to make little practical difference, though; the system went through a more or less complete new installation process, complete with the requirement of entering the Product ID during installation and then of activating the installation.  But then I saw that Comodo Fireway and Avast antivirus were still installed, so plainly it was different from a new installation in some ways.  Unfortunately, the repair installation did not fix the "You must be logged in as an administrator" error -- even though there was now only one Administrator account, and that's what I was logged in as.  So I tried again, this time doing a complete reinstallation from scratch (i.e., not a repair installation).

After doing the complete reinstallation, including (this time) a decision to delete the Ray Woodcock account and make sure that everything was being installed in the Administrator account, I tried again to install AWC.  This time it installed with no problems.