Paypal-Authorization Error 1002

While integrating Paypal I was receiving an authorization error 1002

My NVP header string all the things except paymentaction which can be selected based needs from following url

https://cms.paypal.com/us/cgi-bin/?cmd=_render-content&content_ID=developer/e_howto_api_ECSettlements

Other things needed for header string are

API_USERNAME
API_SIGNATURE
API_ENDPOINT
SUBJECT
PAYPAL_URL
Paymentaction

I used it as "Sale" as mine was a case of st right forward sale

If you are receiving a  result as follows

Array
(
    [TIMESTAMP] => 2013-06-22T10:06:14Z
    [CORRELATIONID] => 5xc75ssx3d7e2
    [ACK] => Success
    [VERSION] => 65.1
    [BUILD] => 6454311
    [AMT] => 23.00
    [CURRENCYCODE] => USD
    [AVSCODE] => X
    [CVV2MATCH] => M
    [TRANSACTIONID] => 9T29872102086351Q
)

then payment is processed successfully