Hi everyone,
 
New to this site and was just wondering if there is a way you can email a drawing to an external party, but somehow attach it as an xref type drawing so it cannot be altered.
 
I need to send a drawing to an electrical contractor for him to put his electrical work on, but want to protect the drawing so it isn't messed about with and just get his layer added to the drawing.
 
I've done xrefs before, but I'm assuming this will be noo good as there won't be a path/link. Can anyone help????
 
Many thanks for any help in advance!

There is no simple way. Any xref can be also opened directly (and modified). You can send a DWF file (instead of DWG) or you can use some IP protection add-on tool like CADvault.

Send him a BMP or JPG file.  He can use IMAGEATTACH to bring it into AutoCAD and draw over the top of it.

Tried a dwf but would be no good as contractor cannot then add his bits on as a layer- looks good for mark ups/annotation but notthing more unless i'm mistaken. Not got IP protection or CADvault..

DWF files can be used as underlays (similar to DWG xrefs) in all newer versions of AutoCAD. You can also advise your contractors to use Autodesk Design Review - a free markup tool based on DWF.
 
CADvault squeezes the selected objects inside a DWG file to a specia "vault" object protected by passwords - you can use multiple levels of passwords to enable reading, copying, editing.

bmp or jpg are also no good as I still can't get his layer onto my original dwg. Know what you saying re IMAGEATTACH and sketching over top, but seems a arse about face way of doing things. Seems this is a big flaw in Autocad unless anyone knows any different I'm on 10 aswell!
 
Maybe autocad12 will be different!
 
Think I'll just lock all my layers in the 'layer properties' and then send him the drawing. He's a trusted contractor of ours so hopefully he won't stitch us up or bugger around with it
 
If anyone else has any useful info on this be good to hear from you.

Gonna do what Vladimir Michl suggests and save the drawing as a dwf then import the dwf into a new dwg as an underlay!
Seems best option. Contractor can then use autocad as he normally would adding his bits n pieces in (on his layers) then when I get it back I can just copy and paste his layer back into my original drawing.
 
SNAPS WORK ON THE DWF UNDERLAY AS WELL WHICH I WASNT EXPECTING!
 
Just thought I'd post incase anyone else is having the same difficulties!

There is no simple way. Any xref can be also opened directly