Error 1706 "No valid source" - one solution found

I've installed and updated Office 2000 as administrator on a friend's
machine. When she used her non-admin account to run any Office program,
she'd get (3 times):

"Error 1706. No valid source could be found for product Microsoft Office
2000 Premium. The Windows installer cannot continue"

.... after which the program would run normally (apparently).

After research, I tried upgrading from Windows Installer 1.1 to Installer 3.
No change. Then I tried removing any part of Office set to "Install on 1st
use". No change.

Then, noticing that the programs ran ok in the administrator account, I
upgraded her (Power User) account to the Administrators group. The
Installer window appeared next time, completed successfully, and has never
been seen since. I've since downgraded her account again (for security
reasons).

Hope that helps someone else out there.

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## PH, London
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