when mIRC 6.2 jumps to the :error goto point, using an $iif causes a /reseterror as seen with this code:

ON 1500:TEXT:.*:*: {
$eval($2-,2)
:error
echo -a $error
msg $iif(#,#,$nick) $error ERROR FAILED
echo -a $error ALSO FAILED
}

the first error will echo just fine but the second error will not evaluate unless evaluation brackets are used and even then any subsequent $error will not contain anything.