"OS X" "windows file sharing" "incorrect password" - Google Search didn't help me, but I figured this but out on my own.
The bug bites when you enable windows file sharing by account. You have to enter the account password -- but it doesn't work!
I think this bug shows up when you migrate a 10.3.9 account, that itself started life with 10.1, to a new machine running 10.4.x using the OS user migration utility. That seemed like a great idea at the time, but in retrospect OS X does not manage machine migration nearly as well as Mac Classic did.
The answer is to go to each user account and change the password to something different. Then change it back to the original password. This fixes things.
There's a similar "incorrect password" bug that shows up on the Win98 side when connecting to a Mac SMB share. I haven't figured that one out yet, I'll try restarting the Mac and see if that helps. I also used the super-occult OS X Directory Access utility to change my OS X SMB workgroup to match the Windows workgroup.
Note that the Windows workgroup SMB browse name is the same as the Bonjour/Rendezvous browse name (machine_name.local).
Jeez, ever since I started migrating my mother from Win98 to OS X I've been running into a torrent of OS X bugs and usability errors. OS X really does have a lot of issues ...
Update 1/1/07: Well, I got bidirectional file sharing working between Win98 and OS X. What a pain! I'm not sure what did the trick. I used the ultra obscure Directory Access utility to change my OS X SMB workgroup name from "workgroup" to the name used by the Win98 machine, I logged in to the Win98 machine with a username that matched the username on my OS X machine, and I probably did a few other things too. It does work, but really this is ugly.