did you double check you POL login setting and make sure POL isn't set to use one-time password? This was something that was an issue back when everyone started linking accounts....think it was getting toggled on by default.

Launch POL, pick your name, and then click the settings button on the left to get to the change settings panel. At top will b e your Member name, POL ID,, the Set Password option, and so forth. At the bottom will be a section for your SE ID and there is a toggle there for using tthe one-time password.

Also, need to make sure the saved POL data on your system is in synch with what is saved at the SE Account Management page. People have mistyped thier password in one of these two places, and this was where the error was getting tripped.