How can we run regtest without transaction fees

Question

We have setup a bitcoin network using regtest mode and found that there is transaction fee charge on each sending Bitcoin.

Is it possible set the payment fee to zero for each transaction?

We found that there is a setting in the conf file called paytxfee. We have tried to uncomment it, but the client complains that its missing.

We are using ver 0.11. How to get rid of the fee for each transaction?

I enclosed is the error message too.

Pay an optional transaction fee every time you send bitcoins. Transactions with fees are more likely than free transactions to be included in generated blocks, so may be validated sooner.
paytxfee=0.00

Answer 1

This is a duplicate - see also Does the Bitcoin Qt client have a minimum transaction fee?

Bitcoin-QT will protect you from sending transactions that are very unlikely to ever be included in the blockchain. If you really want to try sending with 0 transaction fee, you will need to use another wallet software or patch and recompile the code.

It is highly recommended to include some transaction fees. See estimates at https://bitcoinfees.earn.com/ (former "cointape") to figure out how much is needed. Keep in mind that the estimates are very uncertain, they count it's like 90% probability that the transaction will go through within the estimated window - but then there is also a 10% probability that the estimate is off. There have been times where transactions that should have gone through within hours have taken days or weeks to get through, though it's rare.

I often also consult https://jochen-hoenicke.de/queue/ to see what's going on, particularly the "mempool size in MB"-graph may be relevant.