The PDFMaker may have been disable in your Outlook.
To enable it open Outlook.
Click on > Tools > Trust Center
Choose Add-Ins in the list on the left side of the Trust Center window. Choose Disabled Items in the Manage pop-up menu at the bottom of the Trust Center window. Click Go.
Look in the Disabled Items list for Acrobat PDFMaker Office COM Add-In.
If Acrobat PDFMaker Office COM Add-In is in the list, then select it, click Enable, and click Close. Then close and reopen the Office 2007 application.
Hope this will resolve your issue.
Cool!!! These are the exact steps to convert few emails but i used an outlook pst converter application because the no of emails are very large (2600) and attachments are also needed to export. It can be also used to do outlook emails to pdf conversion without need of ms outlook.
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