Did the Prophet have knowledge of the unseen ('ilm al-ghayb)?

Some groups claim the Prophet possessed knowledge of unseen, as for example in this [article](http://www.ahlus-sunna.com/index.php?option=com_content&view=article&id=54) . Indian sub-continent [Barelvis](https://en.wikipedia.org/wiki/Barelvi) say the Prophet possessed knowledge of unseen, too. **Question**: Did the Prophet have knowledge of the unseen (_'ilm al-ghayb_)? During _Hijra_, the Prophet hired a guide for the trip. If the Prophet had knowledge of unseen, he would not have hired a guide. The Prophet would have known all safe routes to _Madinah_. Does hiring a guide for _Hijra_ opposes those who say the Prophet had knowledge of unseen?