This question already has an answer here:
So I've got a weird one...
Whole network kind of went down. Server crashed and the backups don't seem to have worked. A workstation crashed. We have the OST file from the workstation thankfully, but have no idea how to extract data. We honestly just need to get to the contacts. Emails, calendars, etc. are not even desired. Just the contacts.
I hope someone can point us in the right direction of a free solution.