At first I thought that perhaps the user given to the service didn't have proper credentials to establish DDE connections, so I assigned it a administrator user.

Did you try leaving it as Local System account and enabling "Allow service to interact with desktop"?

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
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In reply to Re: Using WIN32::DDE in a Windows Service by BrowserUk
in thread Using WIN32::DDE in a Windows Service by bougon

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