Make sure the file abc.qvd actually exists and is in the place where your document expects it to be. If you moved your .qvw document to another place and use a relative path to the abc.qvd then the .qvw document won't be able to find it.
Another thing that could happen is that the abc.qvd is (still) opened by another application so that the abc.qvd file is locked and can't be opened by your .qvw document.
Thanks for your reply. Unfortunately, path of qvd has not changed. This qvd used to load without any issues previously, but all of a sudden it is throwing error now.
Also regarding another application using the qvd, I tried to rename the file and was able to rename it.Hence I dont think it is used by any other programme.