Attempt to manually create instance gives ERROR with no explanation. html source view shows pop-up

In attempting to manually create a new instance in 12.1.3 install base for the first time, an error appears at the top of the html page upon saving indicating "Error."  There is no explanation in the header of the page.  When I viewed the html page source it showed error indicating a pop-up blocker was active for the browser.  When i checked this, it turned out that it was not turned on and the error was incorrect.  I have checked everything from the SFM setup to the inventory item setup and there is no obvious setup issue.  The only difference