Microsoft Outlook categories that start with "#" are tags in Remember The Milk.
To distinguish tags from lists (which also sync as categories), each tag name is pre-fixed with a "#" in Microsoft Outlook i.e., the tag errand from Remember The Milk will show as the category #errand in Microsoft Outlook.
To create a new tag within Microsoft Outlook, simply create a new category and start the name with a "#". When you sync with MilkSync, this category name will automatically become a tag in Remember The Milk.
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