Could not find any non-coinbase UTXOs to spend

Technology zcashd client
1

Hi, I’ve the following situation:

…
“category” : “generate”,
“amount” : 2.94951130,
“vout” : 0,
“confirmations” : 596,
“generated” : true,
…

but when i go to send them in another uxto I’m not able to perform the operation and I’ve back the next info:

“id” : “opid-ee4cf611-8921-493b-8a49-466d80f5df51”,
“status” : “failed”,
“creation_time” : 1474529817,
“error” : {
“code” : -6,
“message” : “Could not find any non-coinbase UTXOs to spend.”

What does it mean? Thanks in advance for any answer.

2

Were you trying to send to a transparent address? Generated coins must first be sent to a protected address.

3

Ok, I understand. Thanks.