81002: Unspecified Method: Method Specified not Supported

I'm getting the above error response when trying to use paypal express checkout. Below it the pertinent log file. I assume I am on an outdated version of the product but am at a loss as to how to upgrade (our company hired a third party who implemented zen, then they went under leaving me the task of trying to figure all this out).

https://api-3t.paypal.com/nvp
live
Request Headers: array (
0 => 'Content-Type: text/namevalue',
1 => 'X-VPS-Timeout: 45',
2 => 'X-VPS-VIT-Client-Type: PHP/cURL',
3 => 'X-VPS-VIT-Integration-Product: PHP::Zen Cart WPP-NVP',
4 => 'X-VPS-VIT-Integration-Version: 0.1',
)

Request Parameters: array (
'' => NULL,
)

Response: array (
'ACK' => 'Failure',
'L_ERRORCODE0' => '81002',
'L_SHORTMESSAGE0' => 'Unspecified Method',
'L_LONGMESSAGE0' => 'Method Specified is not Supported',
'L_SEVERITYCODE0' => 'Error',
)

If you search the forums for 81002, you'll see several threads which discuss that error, including this one:

http://www.zen-cart.com/forum/showthread.php?t=174165&highlight=81002

What version of Zencart are you using ? You can look in Admin - Tools - Server/Version Info if you aren't sure.

yeah, I've already read those. That's why I'm inclined to try the upgrade.....

Yes, your logs show that you're using an ancient version of Zen Cart.
Upgrading will be the best place to start.

Any other ideas? I'm getting this message too, after a server failure/move and reinstall. I have no idea where to look for a dodgy file, all the likely suspects appear to be the same size files and nothing is missing that I can see.

A logical first place to start would be to compare all your site's files against the originals, or at least against a good clean backup from when it was working fine.
http://www.zen-cart.com/wiki/index.php/Troubleshoot_-_Diagnosing_Obscure_Issues

In the end I had to download the whole zen cart files and reinstall all paypal modules. That sorted it!

Just had this email
ALERT: PayPal Express Checkout Error (81002)
81002 Unspecified Method - Method Specified is not Supported

Im running 1.3.9h and recently installed Paypal Express Checkout.
Any ideas as to what I can do to rectify this please?
http://www.towerhousedolls.co.uk/

One other question to do with Paypal Express.
The Check out with Paypal button is too high and obscures the text. Is there a remedy?
Can be seen here http://towerhousedolls.co.uk/index.php?main_page=login

Pookiehair:

Just had this email
ALERT: PayPal Express Checkout Error (81002)
81002 Unspecified Method - Method Specified is not Supported

Im running 1.3.9h and recently installed Paypal Express Checkout.
Any ideas as to what I can do to rectify this please?Without seeing the debug logs from the transaction attempt that triggered that, we can't help you. You could ask PayPal to check on their end to see if maybe they can try to look up the cause for you. It may take them awhile. https://www.paypal.com/mts

I didnt have the debug on at the time but have turned it on now so will see what happens next time.
Have contacted Paypal too.
The order confirmation & payment came through ok. Its just the email that's puzzling me saying
81002 Unspecified Method - Method Specified is not Supported.