If that doesn't do the trick, then you will have to try other methods to get QuickTime to launch properly. On a Mac, it may simply involve quitting the process. To do this, go to your Activity Monitor and find QuickTime Player under the 'Process Name' column. Click on QuickTime Player, and then click on 'Quit Process.' Solution: Use a common movie format If you want to insert a movie in an Office for Mac file, such as document, worksheet, or presentation, or attach a movie to an email message and then play the movie in Office for Windows, use a common movie format, such as MPEG 2, MPEG 4, or AVI. Q2: Quicktime Player doesn't work on Mavericks. I have problem with Quicktime after I update the system OS X Mavericks. Now it doesn't work. I download Quicktime 7, so I can open the videos, but I cannot make it default. My problem some videos in the web do not work. This appears to be an under-the-hood change designed for Mac OS X. Oct 29, 2019 QuickTime is now more exclusive to Mac users as Apple has dropped support for the Windows version. So, why waste time with it if you're a Windows user? Re-Encode Video Using VideoProc - (Highly Recommended) If none of the above-mentioned solutions work for you then you should rely on this final one.

Quicktime For Mac 10.7.5