Solved by myself -> I forget to define a storage pool ! Thanks a lot anyway ! <div class="gmail_quote">On Tue, May 19, 2009 at 6:31 PM, Francesco Latino <<a href="mailto:francesco.latino@gmail.com">francesco.latino@gmail.com</a>> wrote: <blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Hello, I have a running KVM virtual guest "demo1" with a defined disk at path /guests/mydisk.img. But when I run conn = virConnectOpenReadOnly(NULL); path = "/guests/mydisk.img"; virStorageVolLookupByPath(conn,path); I got the error " ibvir: Storage error : invalid storage volume pointer in no storage vol with matching path " what am I missing ? Thanks, Francesco </blockquote></div>