Startup of Media Composer w/out an external or secondary media drive gives the following error:
"No media can be written to any mounted drive. Please check write permissions."
Connect a fast external drive or if a Mac Pro, add an additional internal SATA disk.
Default root access (/) of the system drive is Read Only for all users (but root). You can change the default to read-write for all users, but this does affect the security of your mac drive and allows users to create and save content to folders where normally they are protected from doing so. Please note that if you change this and then run the disk utility's fix permissions, you will have to do this override again.
To perform this anyway:
1. Highlight the Macintosh HD system drive.
2. Right click and chose Get Info (cmd + i)
3. Click the lock in the bottom corner to allow changes, authenticate.
4. Click the text "Read Only" in the Privilege column next to Everyone and change to the privilege to Read & Write.
5. Close the dialog, and start-up Media Composer.