What may be the reasons for a Domain Name Transfer Failure?

1. The status of the domain is locked, thus making it impossible to be transferred. In this case, the registrant must contact their current registrar to change the status.
2. The EPP code provided is either wrong or not full. In this case, the registrant must, again, contact their current registrar to obtain the right code. In the cases, where the registrant generates their EPP code from the control panel, they should make sure they are not copying some additional symbols that are not part of the code. For better results double click on the code with the left button of the mouse, press Ctrl C and then paste it with Ctrl V. This way you avoid including any spaces.
3. The domain name was registered or renewed less than 60 days ago. In this case, there is nothing you can do, but wait for the 60 days to pass (in the case of a renewal the period is 45 days) and then try again.
4. You have no access to the administrative email.
5. You have access to the administrative e-mail but you haven't received an e-mail with an authorization request from the new registrar. In this case, you should contact the new registrar and inform them, so they can reinitiate the order. 
6. You have access to the administrative e-mail but have forgotten to check it and to click on the confirmation link sent by the new registrar. If you are too late and the link has already expired, then you have to relaunch the transfer.
7. You have access to the administrative e-mail but you have forgotten to check it and to click on the confirmation link sent to you by the registry.
8. You have an ID protect feature. The ID protect won't allow any personal information to be shown to the public, which hides your administrative e-mail as well. If the e-mail is hidden, then you won't receive the needed confirmation e-mail. 
9. By deactivating the ID Protect feature, you will be able to receive the authorization request e-mail. 
10. The current registrar is denying a transfer. If this happens, then the registrar must provide you with a legitimate reason, as to why they are denying the transfer. Some of the reasons may be one of the previously mentioned above.