Bonjour et merci pour les réponses.
Pour ce qui est de réinstaller la machine, et tout les logiciels et utilitaires la derniére fois ça m'a pris quasi une semaine, alors je préfére pas, j'ai donc cherché dans l'imonde bouzin de suport apple et j'ai trouvé l'explication ci dessous.
Je l'ai pas encore testé mais a priori ça pourrait répondre à mon probléme...et éviter a d'autre de réinstaller toute la machine quand y a juste un pb sur compressor :
voici la note d'apple :
Final Cut Pro and DVD Studio Pro: Compressor - Cannot submit job from Batch Window
In some situations submitting a job in Compressor fails even though a valid source, preset, and destination have been added.
Symptom
The Submit button is dimmed in Compressor's Batch window, or a message appears stating "Unable to connect to background process" when submitting a job. This can occur due to an issue during Compressor's installation.
To prevent this, either completely disable or temporarily remove third-party antivirus software or disk utilities which may run background processes during Compressor's installation.
Products affected
Compressor 1.0, 1.0.1, and 1.2 (part of Final Cut Pro 4 and DVD Studio Pro 3)
Solution
If you have Mac OS X 10.3 or later, update to Compressor 1.2.1.
If the issue continues:
Click the Finder in the Dock.
From the Go menu, choose Go To Folder.
Enter "/Library/Receipts" and click Go.
If present, drag files which contain the name "CompressorUpdate" to the Trash.
From the Go menu, choose Go To Folder.
Enter "/Library/Frameworks" and click Go.
Drag the file "Compressor.framework" to the Trash.
Go to either the Final Cut Pro or DVD Studio Pro page and download the Compressor 1.2.1 update (you will need to have your serial number).
Install the Compressor 1.2.1 update.
If this does not resolve the issue and you have both Final Cut Pro 4 and DVD Studio Pro 3 then do the following:
Uninstall Final Cut Pro and DVD Studio Pro.
Reinstall Final Cut Pro 4 and download and install all updates.
Install DVD Studio Pro 3 making sure to pick "custom" and unchecking Compressor to install on DVD Studio Pro and A.Pack.
If only one of these applications is present then uninstalling and reinstalling the single application should resolve the issue.
For Mac OS X 10.2 to 10.2.8
In most situations, updating to Compressor 1.1 should resolve this. You can use Software Update in System Preferences to install the updates. Note: The Pro Apps Support package (ProKit Framework) must be installed first. Once the Pro Apps Support Package is installed, then click Check Now in Software Update again to see the Compressor update.
If the issue continues, it may be because DVD Studio Pro 2 was installed after installing Compressor 1.1. DVD Studio Pro 2 installs some components that do not work with Compressor 1.1. To resolve this, follow these steps:
Click the Finder in the Dock.
From the Go menu, choose Go To Folder.
Enter "/Library/Receipts" and click Go.
Drag the file "CompressorUpdate1.1.pkg" to the Trash.
From the Go menu, choose Go To Folder.
Enter "/Library/Frameworks" and click Go.
Drag the file "Compressor.framework" to the Trash.
Go to either the Final Cut Pro or DVD Studio Pro page and download the Compressor update (you will need to have your serial number).
Install the Compressor update.
