Error editing pictures

[bdietz]

I have been trying to use the Edit Picture feature to apply the same screen tip to an image that will be used in multiple topics. I click the "Apply the alternate text and screen tip to all image references." When I try to save, I get the attached error message, stating the "Object reference not set to an instance of an object."

I do have a style applied to the picture. Any idea what is causing this error?

Thank you