Problem solved. It seems the user already existed. I have a follow up question but will post it in another section.

Thanks to all.

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Hi,

I am trying to add user IUSR_MyMachineName in Windows XP via Start > Settings > Control Panel > User Accounts. After entering the user name and indicating that it will be a limited account type, I press the Create Account button, but nothing happens.

I am logged in as an Administrator.

Any idea what may be the problem?

TIA,

Alex