The documentation for WWW::Mechanize says tick and untick accept the following parameters:

$mech->tick( $name, $value [, $set] )

$mech->untick( $name, $value )

I therefore suspect that what you really need to do is the following:

$self->{'agent'}->untick('newsletters', 17);
$self->{'agent'}->untick('newsletters', 65);
$self->{'agent'}->untick('newsletters', 34);
$self->{'agent'}->untick('newsletters', 71);

[download]
Or more succiently 
$self->{'agent'}->untick('newsletters', $_) for (17, 65, 34, 71);

[download]

However, not knowing the form or the html that you're accessing, I can't say for sure what you're doing incorrectly. Can only go on the way it looks.

In reply to Re: How do I uncheck a checkbox with WWW::Mech? by wind
in thread How do I uncheck a checkbox with WWW::Mech? by hesco

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