Sometimes the button says "Check for new mail in Inbox" and at some other times it says "Send/Receive". If my observation is correct, when the account status is green (sync'ed), it says Send/Receive and when the account is in process of sync'ing, it says "Check for new mail in Inbox".

What is the difference in the two.

Is there any way to sync a specific folder. I do not see any option for this when I right click on the folder. This may resolve lot of problems with sync'ing of specific folders that people are facing, including me with yahoo web mail.