Outlook Express cannot open because another instance is

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Every time I try to upgrade Windows XP PRO SP1, by installing SP2, or SP3,
I get the following problem when trying to switch identities in Outlook Express.

First Outlook Express window closes, and disappears.

Then if I click on the OE icon to open it, I get the error message
"Outlook Express cannot open because another instance is ... "

If I go to "Task Manager" it's not running anywhere I can see it, or kill it.

After many wasted hours, reboots, re-installs of XP, SP2, SP3,
on a hunch, I installed the Internet Explorer 6.0 update KB969897,
and this appears to have resolved the problem.

Hope this post will help save someone else's sanity.

Xiu Zhang

Thanks for your sharing.

But here is the forum for Exchange Server.



Hi there,

1.) update KB969897 - Mentioned above - did not resolve the problem as it turns out.
2.) On Task manager - there is no msimn.exe running that we can kill - we checked that option first.

For now I have gone back to running Windows XP PRO with SP1 and with only an update to allow us to change user identities (KB911567).
In this condition, I do not get freeze ups when changing identities, however I do not get the additional security.

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