In your other thread about this ( https://www.bleepingcomputer.com/forums/t/655679/cant-see-share-folder-on-windows-server-2003-or-windows-8/ ), I suggested a procedure that needs to be followed for a windows system to successfully authenticate to a Shared folder on a (recent) MAC. How did you get on with that? (A quick word to the wise Helping someone when they are running concurrent threads for advice and not providing detailed feedback is not easy, and sometimes the helpers may trip over each other. I'd suggest we stick with this thread and get the other one closed with a referral to this one.)
The suggestion is for exactly this issue, but as I say I cannot verify that it is relevant to the older MacOS. Did you understand the instructions, were you able to find equivalent settings in the older OS? Did you select the account that you want to authenticate with, re-enter the password for that account, but the connection attempt still failed?
You can keep AFP, as sfletetechguy says you need SMB, and you also need my settings to account for the poor password encryption on there Windows systems. The accounts you need to use are the user accounts on the Mac, and you separately need to enable each account to be compatible with Windows using my setting. Of course this all falls apart if that setting does not exist in 10.5.8...