los correos recibidos se quedan encolados hasta que lo libere manualmente
El mensaje, que muestra es:
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421 4.4.0 [internal] no MXs for this domain could be reached at this time
421 4.4.0 [internal] no MXs for this domain could be reached at this time
421 4.4.0 [internal] no MXs for this domain could be reached at this time
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he conectado por consola desde el servir y si hay conectividad via telnet al puerto 25
espero sus comentarios