"My 4-year-old list is set up to probe every six
months."

there are two types of probes.

one is the active probe as part of the renewal
process.

this is probably the one you refer to.

there is also passive probing.

they are useful for many reasons, mainly subscriber
convienence and error message bounce reduction.

while i will be happy to give the details if needed,
it would better for listowners to read the pertinant
section (4.9) in the listowner manual.

bill salmon

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