I purchased a new Black and Decker corded string trimmer---14" 6Volt. The only part I had to attach was the guard. I could not slide it on as the wire edge guide was in the way? The only way I could get it on was to pull the wire edge guide all the way out. But then I was not able to retract it as the manual says it is retractable. Help!!

barbiem, May 2012