Manual archive from Outlook doesn't work ?

Hi,

When I select few large emails (10 MB+) in my outlook and move it into Vault using the EV plugins 9.0.4 on my Outlook 2007 SP3,

For example I go to TOOLS, Enterprise Vault, and click ‘store in vault’ for this email, I can see it has the clock and box icon, then after 2 minutes it goes back to normal and didn’t move into the fault ?

Any idea of how this could happens ?