trouble retrieving private key

[Anna1406]

been trying to get my private keys from my bitcoin core wallet but 'dumpprivkey' always returns 'error-5'.
the only thing i can think of is that i'm using the wrong public key but i'm not sure where i'm going wrong. i tried 'getaddressbyaccount', 'getaccountaddress' and 'validateaddress' in combination with the receiving address i used for the transaction but none of them will give me a public key that works in 'dumpprivkey' 
the only other thing i could see affecting things is that i'm offline when i try to get my private keys but i don't see how this would make a difference
at a total loss here so any help is appreciated

[DannyHamilton]

the only other thing i could see affecting things is that i'm offline when i try to get my private keys but i don't see how this would make a difference

You don't need to be online.

been trying to get my private keys from my bitcoin core wallet but 'dumpprivkey' always returns 'error-5'.
the only thing i can think of is that i'm using the wrong public key but i'm not sure where i'm going wrong. i tried 'getaddressbyaccount', 'getaccountaddress' and 'validateaddress' in combination with the receiving address i used for the transaction but none of them will give me a public key that works in 'dumpprivkey'

You shouldn't be using a public key.  You should be using the bitcoin address that was generated by the wallet.

Code:

dumpprivkey 1YourBitcoinAddressGoesHere

Where: 1YourBitcoinAddressGoesHere is the bitcoin address generated for that wallet file for which you want the private key.

[Anna1406]

thank you. seems like i was working with bad instructions. worked fine this time