... yet it cannot be repeated often enough.
If you are submitting queries to agents or sending work to magazines and journals, and you use one of those spam filters that requires them to get permission to respond by clicking through to a third-party site, you will never, ever, ever hear from them about your written work. Maybe not even if they're emailing you to request a partial or accept your short story.
If you are using one of those filters and not getting any response to your submissions - not even the formality of a rejection notice - that might be the problem.
If you really get that much spam, set up a separate free online account that you only use for submissions. Just use your name (pen name is fine), not something catchy or cute. Gmail seems to popular with everyone. Hotmail and Yahoo also work. There's nothing off-putting or unprofessional about JoeSchmoe@gmail or Joeschmoe@yahoo
I have been known to go out of my way to keep lines of communication open with our submitting writers, but if I get one of those requests for validation, I'm done. And I know I'm not the only one.