Hi Mandeep
I assume that you are opening the separate edit form from qListView which aggregates multiple lists and encounter this error. We have seen this happen in the past due to conflict with "ID" as SharePoint uses this in the query string a lot, especially if you are creating edit form by re-using the form pages (by hiding OOTB list form and use qListForm).
Even if this is not the case, you can avoid this problem by changing your URL query string "ID" parameter to something different, such as "PID" or "OID" and etc. Then you need to launch ezEdit for the qListForm and change the default HTTP paremeter ID (I believe it is under Display tab in the ezEdit window) from "ID" to "PID" or "OID". This should work without seeing this error.
If the previous assumption is true, then you need to do one more configuration change, in your qListView where you aggregate mulitple List, change the default HTTP parameter ID from "ID" to "PID" or "OID". When you right click on a list item to launch "Edit Properties" or "View Properties", it will launch the right edit form page with the right query string id.