Once again, you should only use a filter if you have DSL.
Assuming you have DSL, and you are not using a filter with
your alarm system. Then the following will happen: Your DSL service will be
very very slow, and/or intermittent. Worse
of all, your alarm system will not worked when actually needed.
Only if you have DSL service. With Fios you don't need it
anymore.
If you have DSL service, then your alarm system does need a
filter. But don't use a regular filter,
it needs a different type of filter, such filter should be provided by your
alarm system provider. In most cases your internet service provider will only
send you regular filters.
If the Verizon Email filter flagged a non spam email as spam, you can send an email to spamdetector.update@verizon.net to report the mistake and ensure it does not happen again. to report the mistake and ensure it does not happen again.