Can't SSH: Permission denied (publickey,password,keyboard-interactive)

[atomant]

Hello good people!

 I'm trying to setup piCore to run on my Raspberry Pi Zero 2 W. Managed to boot, managed to connect to WiFi, SSH is running. This will be a headless setup so I'd like to connect remotely. The problem I'm facing is, if i try to connect to the system using Putty from a Windows machine and specify "tc" as login name and "piCore" as password (without the quotes, of course), all i get is "Access denied". If i try to connect from the system itself to itself, i get "Permission denied (publickey,password,keyboard-interactive)". As i already set up piCore on earlier rPi Zero versions and after connecting to my WiFi network SSH just worked out of the box, without the need for any fiddling, I'm not sure what i might have done wrong. Any pointers what i should check?

Additional info: I'm running piCore version 13.1.0, I'm booting from an USB drive, i'm using openssh. I'd like to use the simple login name/password approach, don't wish to move around keys and whatnots. I didn't change the password of the tc user, after some unsuccessful tries i did try using passwd to set it to the default piCore, just in case, but it did not change anything. I tried googling around for answers but frankly, I'm not sure what to look for.

[atomant]

Now it works but why it does is puzzling to me. I will leave the post here, perhaps it will help someone in the future, but i have my doubts.
Here's what i did: i enabled logging in sshd_config and ran syslogd. Tried to log on with SSH and checked the log and it was saying the password is wrong. Here i got suspicious and i used passwd to change the password to something else than "piCore", tried logging in again and tadaa, success. Then, out of curiosity, i changed the password (back?) to "piCore" and tried logging in again and it worked with that too. Quite confusing. At first i thought, perhaps the tc user didn't have a password at all somehow and since by default, empty passwords aren't allowed by SSH, it would not allow logging on (i did try this too). However, as i wrote above, i did try passwd-ing to "piCore" and it still wasn't working. But when i changed the password to something else and then back to "piCore" it now works. Must be woodoo.