ms project london - Project integration with Sharepoint

Hi guys,

I am trying to sync in multiple project plans ( on a MS Project 2010) with sharepoint 2010 on an existing list, but every time I try and sync in a project plan it automatically creates a new sharepoint list, because the previous one ( on which I initially intend to save the plan) is already in use.

I created a new sharepoint list and managed to sync it with a project plan. However I then created another project plan and tried to sync it with the same sharepoint list and this error occurs:

" The task list was synchronized to a different project plan. If you continue with the synchronization the task list will be appended with the project plan"

Any idea what to do ?

Thanks