This POP3 server does not seem to support encrypted passwords. If you just set up the account, please try changing to 'Password, transmitted insecurely' as the 'Authentication method' in the 'Account Settings | Server settings'. If it used to work and now suddenly fails, this is a common scenario how someone could steal your password.
Zda se, až toś ten POP3-serwer njepódpěra skoděrowane gronidła. Jolic sy konto rowno zarědował, wubjeŕśo pšosym 'Gronidło, njewěsćej pśenjasone' ako 'awtentificěrowańska metoda' w 'Kontowe nastajenja | Serwerowe nastajenja'. Jolic to howac funkcioněrujo a něnto naraz nic, jo to zwětšego pśiznamje, až něchten by mógał wašo gronidło kšadnuś.