Following these instructions have proved to be little help, many of the important and critical details seems to have been left out!
For example, during the base string creation: the OAuth parameters have to be sorted alphabetically. Further there are issues with how characters are URL encoded, e.g. they have to be in the upper case format.
There are many, small but critical details like these that are missing from the above online yahoo OAuth guide. Due to this I have had to rely on information obtained from extensive searching online, pulled from various forums and blogs.
I’m using C# and asp.net with Visual Studio 2008. The OAuth helper Class I am using has been obtained from here:
It is a very trivial task, get users list of email contacts (post consent).
Out of using three API's (Google, MSN, Yahoo):
MSN has worked, but their "Security Scopes" means that the ONE thing I require (the emails) are not retrievable! and the process of getting the required access is almost deliberately hidden/obfuscated.
Only Google's has worked with Zero issues and worked perfectly. Why does Yahoo and MSN have to make things more complicated then required?
Sadly its this very kind of frustration that leads developers to use screen scraping in order to complete the required task.