There's no fixing it because there is no love for the brand. People have Yahoo email addresses for the same reason they have Hotmail - they got their free email account before Gmail was available and it is too much trouble to change it.
Bartz's hiring was a classic case of drafting a CEO based on who is available rather than fit - there was virtually no overlap between Autodesk's business model and operations and Yahoo's. Hopefully, she will find a much better circumstance in her next role.