That particular transaction is 10.9kB larger than the default maximum allowed transaction size which is 100,000 bytes.
There must be a lot of inputs included and the server you've connected to had rejected your transaction.

I guess you're sending all of your wallet's balance....?
But anyhow, try to remove some of the low-value inputs by displaying the Coins tab (View->Show Coins),
then freeze (right_click->freeze) the one's with very low amount to exclude them to your transaction.

Alternatively, you can select which inputs to spend from using CTRL+Left click to select (highlight) your preferred inputs then Right click->Spend.
Then the send tab will be displayed with those inputs already included.