DIAGNOSIS The sharpener is not fully seated or is being installed on an incompatible bar. The CS1500 requires the specific Oregon PowerSharp bar.
FIX Ensure you have the correct Oregon PowerSharp bar installed. To attach the sharpener, align the red guides on the sharpener with the raised rails on the side of the bar and push firmly until it clicks securely into place at the tip.
IF THAT DIDN'T WORK Check for debris or damage on the bar's rails or inside the sharpener's guide slots. Even small wood chips can prevent a proper seat.
HEADS UP The sharpener is only for touch-ups. If your chain is very dull, manually sharpen it first, then use the PowerSharp system to maintain the edge.