I recently upgraded three C1000-8FP-2G-L switches from 15.2(7)E4 to 15.2(7)E6. After the upgrade the webui was giving me the dreaded "404 not found" error. I've tried downgrading back to 15.2(7)E5, then 15.2(7)E4, then 15.2(7)E3 and none of the previ...