Via which method? A double click on a date?
Does it work via the New menu?
What changed since "suddenly"?
Are you synching with a mobile device?
Did you reboot?
Does it work in Outlook Safe Mode?
Start-> Run; outlook.exe /safe
If so, your issue is probably caused by an add-in.
For further details see;
http://www.msoutlook.info/question/88
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Robert Sparnaaij [MVP-Outlook]
Coauthor, Configuring Microsoft Outlook 2003
http://www.howto-outlook.com/
Outlook FAQ, HowTo, Downloads, Add-Ins and more
http://www.msoutlook.info/
Real World Questions, Real World Answers
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"Hmmmm" <(E-Mail Removed)> wrote in message
news:E9AA9BB5-CCB2-44B7-9919-(E-Mail Removed)...
> Suddenly I cant click to open a date in Outlook Cal to add new events.
> Outlook 2003 in month view. Any ideas what happened or how to fix??