Is there any open source Microsoft Project MPP viewer?

We know that .mpp file extension is a proprietary file format. But, Is there any open source viewer which work with these kind of files?

Solution 1:

Project Libre has superseded OpenProj and claims Project 2010 compatibility.

http://www.projectlibre.org/ is the homepage

http://en.wikipedia.org/wiki/OpenProj#Fork_-_ProjectLibre gives some history on how OpenProj forked to give rise to Project Libre.

Solution 2:

Try MPP Viewer. It works great.

Solution 3:

OpenProj does work. You'll be able to print an MPP file to a printer or PDF from there. For unconfidential project files you may also find the online converter sites useful.

Solution 4:

I do not think there is an open source viewer on the market. But if you need a viewer to open all versions, you can try the Light version of MOOS Project Viewer. This one is free but limited in functionality. The full version has more features.