I am trying to create a KareNSupport email address and every service says that it's already in use. I have tried gmail, hotmail, att, mail.com, everyone I can think of.

I've tried adding numbers behind it and in front and adding another word... to NO avail!

I used one of the services that looks up if it's a valid email and it returned that there is no address of that name found.

Yes, I have tried all lower case also...
Is there a way to block or reserve a string of characters so it cannot be used?

Or what can I be doing wrong?

Insight please... TIA

Basically you get what you pay for, so a free email services, as you have described, if all based on first come first served.
If you are really after this name, why not look at buying the domain name and then you can have any bit at the start you want.