Lifetime of a refresh token

Hello, We are using OAuth2.0 to pull reports from Adwords. We wonder if a refresh token is always valid after it is granted. If not, in what kind of conditions a refresh token become invalid? Thanks. -- -- =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~ Also find us on our blog and Google+:

Re: Lifetime of a refresh token

Hi, Our OAuth 2.0 Authentication guide provides information on access and refresh tokens. An OAuth 2.0 refresh token does not expire. Refresh tokens are valid until the user revokes access. Regards

Re: Lifetime of a refresh token

Thanks for replying. The reason I asked this question is we met the error "AuthorizationError.USER_PERMISSION_DENIED" when using access tokens to pull reports from AW. It is weird, because it worked before. After we got and used a new refresh token, the error is gone. Hence, we suspect somehow

Re: Lifetime of a refresh token

Adding to Nadine response A token might stop working for one of these reasons: 1) The user has revoked access. 2) The token has not been used for six months. 3) The user account has exceeded a certain number of token requests. There is currently a 25-token limit per Google user account. If a user