If it is about unblocking an attachment sent on Gmail then in that case, it is advisable to open the Email that contains the blocked attachments. Further, the user should click the option “show content.” The Email attachment will then be accessible for you. If you are still looking for more information or help then you should get connected with the certified Gmail technicians they can be reached for help as and when needed. Lines are open for assistance all the time. Other than this you can easily get solutions for many other problems related to the Gmail set up.