regarding cad document

hi gurus,

i am using inventor 11 and the problem is i want to upload existing document which is available on my desktop to dms...

when i opening that existing file and log on in sap and then click on cad-view option , it directly open sap window and when i want to check in this existing document, it is showing error..

<b>abc.ipt No documents are assigned to this file.</b>

thansk

amit