I am using v0.11.2; Does this version have "zapwallettxes" or "abandontransaction"? If not, should I back up my wallet, then remove the current version, and then download a newer version? Thank you for your help DannyHamilton. I appreciate it greatly.
abandontransaction wasn't added to the wallet until release 0.12.0 I think, so you'd have to upgrade if you want to use it.
zapwallettxes was added in vesion 0.9.0, so you should have access to that.
To use zapwallettxes, you'll need to shut down your wallet software. Then from a command line in your operating system, you'll need to start it back up with -zapwallettxes as a command line parameter. The method for doing that will depend on what operating system you are using (Apple OSX? Some version of Linux? Some version of Windows?)
The wallet will remove all transactions, and then scan the entire blockchain looking for confirmed transactions. All the confirmed transactions will be found in the blockchain and will therefore be restored to the wallet. All the unconfirmed transactions will not be found in the blockchain, and therefore will not show back up in the wallet. Any bitcoins that were sent with the unconfirmed transactions will therefore be back in your wallet and ready to spend again.
If you decide to upgrade to version 0.12.0 or newer, then in the "Debug Window" found under the "Help" menu, you can enter the following command in the "Console":
(Replacing TXID with your actual transaction ID)