It might be possible to export contacts from Microsoft Windows Address Books (*.wab) to a iCalendar calendar file (*.ics) with some good e-mail and contact management software like Outlook. Sometimes, you need to use a CSV file type as a intermediate step between those two file type.
Convert Microsoft Windows Address Book to iCalendar calendar file format (Microsoft Outlook, Apple iCal).
We have found one software suitable in our database for this conversion.
Microsoft Windows software - convert wab to ics on Windows
An e-mail management tool distributed with Microsoft Office suite
Convert from wab file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.