You need to become familiar with how Bitcoin works at a lower level to understand the problem.

For simplicity think of it like this:

You wallet could either contain one $100 bill or it could contain 10,000 1 cent coins (the latter situation very likely if you are using faucets or getting tiny amounts of bitcoins from some websites "paying" you).

If you are wanting to send 10,000 1 cent coins it is a bit like the merchant going "sorry - you need to pay me in notes".

So assuming this is your "real problem" you will have to perhaps get some help to "clean out the dust" in your wallet (and maybe not continue doing the same thing).