Returned mail: Data format error

[Mail Delivery Subsystem]

This Message was undeliverable due to the following reason:

Your message was not delivered because the destination computer was
not reachable within the allowed queue period. The amount of time
a message is queued before it is returned depends on local configura-
tion parameters.

Most likely there is a network problem that prevented delivery, but
it is also possible that the computer is turned off, or does not
have a mail system running right now.

Your message was not delivered within 3 days:
Host 158.97.218.16 is not responding.

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<czman na linux.cz>

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