I have been searching the forum and I can not find a solid answer to this question: Is there a way that anyone can stop a transaction before the confirmations have been made. For example; I pay Joe Dip 1.1 BTC for a domain name. I can see that the transaction is waiting confirmation in the block chain, however there are no confirmations yet. The seller can also see that the transaction is waiting for confirmations to come through. Once we are at this point is there anyway that I could stop the transaction?
Not if the transaction is valid (signed) and the receiver has already seen it. Lets assume Im Joe Dip here and you send me 1.1 BTC without a fee. Currently thats a bad idea, but you say you are sorry and I believe you.
Now it would take a long time for the transaction to get a confirmation. I could also happen, that the
entire network forgets about the transaction and it essentially never happened. I can however - and would in this case - remind the network about your transaction. For 1.1 BTC worth I would probably write a small script that does this every 30-60 minutes. You can now remove the transaction from your own wallet, but I will keep reminding the rest of the network until its confirmed. This will make it almost impossible for you to issue a different transaction that sends the coins elsewhere.
If we both agree that the TX should be removed and redone. I would not write nor start the script. You remove the TX from your wallet and we both wait a few days until the network forgot about it. This essentially "stops" the transaction, unless someone else rebroadcasts it for some reason (or none at all).
If the transaction pays a reasonable high fee, you can remove it from your wallet all you want. Chances are it gets confirmed anyway.