Why did I get the error "You have requested an outdated version of PayPal. This error often results from the use of bookmarks" in Outlook Wizard?

You received an error message saying that you requested an old version of PayPal.

This error happens only if you choose the Basic payment type when creating a button, because there is a space between "cmd" and "=" in the code.

Use one of the other payment types, such as Product, Service, eBay Auction, or Donation.

See also:
PayPal Payments Standard integration guide
HTML Variables for PayPal Payments Standard