You can remove any file from the Shared Documents folder.
To delete a file, follow these steps:
Click the Groups tab on the left navigation bar.
Click the Group Memberships icon. The Active Memberships page appears.
Select the group in which you would like to delete a file. The Group homepage appears.
Click the Shared Documents button. The Shared Documents page appears.
In the Modify column of the file you want to delete, click the delete link.
Note: Once a file is deleted it is moved to the Recycle Bin where it can be restored or purged later.