The watermark is integrated into the photo, i.e. the pixels in the photofile itsself are modified. This is to prevent users to copy-paste the image and use it for purposes you do not want.
If you want to remove watermarks, the only way is to activate the ‘save source files’ options in Table IX-H. Then you can ‘Remake files’ when the watermark settings are changed/turned off.
The ‘save source’ should be ON before uploading! If not, you can recover from this situation by ftp’ing your photos to the server again, into your ‘depot’ diectory ( See the Import Photos screen to find out where that is ), and import them with the ‘Update photos’ checkbox on.