OLM Converter Pro is intended to help you migrate emails from Outlook for Mac to other email clients, such as Apple Mail, Microsoft Entourage, Mozilla Thunderbird and Postbox. In this regard, the tool can convert not only your messages with their attachments but also your contacts and calendar entries. Good news is that it does not alter the original folder structure of your inbox as well as nested messages.
This email converter is actually very easy to use. In many respects, it is like a wizard that takes you through all the steps of the conversion process. Firstly, you need to import the source OLM files, and, luckily, batch operations are supported. Secondly, you can pick one of the target formats, although Apple Mail comes selected by default. Thirdly, you can choose the type of items you want to convert. Finally, you can proceed to convert your files. The time it takes will logically depend on the size of the source files and the options you have chosen; still, the conversion is carried out smoothly.
Although this tool works exactly as its developer claims, it does have some limitations. For instance, it cannot directly export emails from an Outlook Mac database. Moreover, it does not support merging all contacts from multiple mailboxes or all Calendar items to a single iCall.
All in all, OLM Converter Pro makes migrating from Outlook to other email formats extremely easy and lossless. Nevertheless, there is a more powerful edition, called OLM Converter Ultimate, which can overcome some of the limitations previously mentioned. Fortunately, there is a trial version of OLM Converter Pro but it is limited to recovering only 10 messages from each folder.