Export Outlook for Mac 2011 mails to Postbox Windows

It seems too old question I hope you may find right answer for the same.

Here is simple process for migration

Import email from Outlook 2011 to Postbox

1. Please Quit Postbox if it is currently running.
2. In Outlook 2011, select the folder you wish to import into Postbox. Go to Edit | Select All to select all of the message in the folder.
3. Drag and drop the selected messages into a temporary folder in a Mac Finder window. This will export the messages to eml files. Outlook 2011 shows no progress during this operation and it may take a long time depending on the number of messages.
4. Open Postbox and install the Import/Export Add-on from http://postbox-inc.com/extensions
5. After installing the add-on, use the "Import All eml files from a directory" menu item to import the eml files in the folder you dropped them into.
6. Your mail will now be found in the Local Folders account, within a folder that has the same name as the folder you created in the Finder

For other mail client try

https://support.postbox-inc.com/hc/en-us/articles/202200000-Importing-Email-from-Outlook-2011-Mac-

If you want to convert OLM file to PST file without any data loss then OLM to PST converter software is the best tool for you. This software is capable to convert each & every emails, contacts & to-do-list from OLM file to PST file.

Try this a complete package of olm to pst converter tools to convert olm in to pst http://www.imergetools.com/olm-to-pst-converter.html