We had an issue where migrated users could still log into the Minecraft client with their username and old password. This was problematic if your account was formerly compromised, because changing a migrated account's password only changed the Mojang account record, not the old Minecraft record.
Now, when a migrated user logs into the game client, they must do so in the same manner as logging into Minecraft.net: with their email address and Mojang account password.
The other benefit to this is that people who try to log in as you would now have to use your email address, instead of the username that they can see.
I'm in the same boat. I migrated over a month ago and since then I've only been able to log in using the game client. Minecraft.net/play wouldn't work at all. I've done everything recommended in this forum and on help.mojang.com I also contacted Mojang via help.mojang.com well over a month ago. But since you guys are 2 months behind in your support tickets does this mean I'm going to have to go another month without Minecraft?
I cannot log in to my Minecraft account on the site or in the client! I can log into my Mojang account on https://account.mojang.com/ However. But I cannot do anything else. I all wish to do is play Minecraft! but it comes up with "Login failed" Every time I try to use my e-mail and password in the client and on the site it says that my email or password is incorrect!
I have the same exact problem except I can't login to anything. It's like my password was changed, because due to cache I'm still on Minecraft.net, when I try to change my password it tells me my original password doesn't work anymore. When I try to get a password reset email sent, I don't receive an email, even though on Minecraft.net it shows that my email is still the same. I know my account wasn't cracked or anything because I had a secure password. Marc, please fix this there are a lot of others with the same problem.
Migrated months ago. Couldn't login to minecraft.net or mojang.com because I don't know the email I used. Now I can't login to Minecraft. I sent an email to Mojang, no response. Nothing on the topic on the help page. No servers for me. Well, cracked servers. Yay.
PLEASE just add an option on login screen with Forgot email?
Then you enter old username and password and you get your email.