Name changes in Minecraft can cause various issues depending on the version of the server. The information below will help you understand what needs to be done to transfer your ingame property to the new name.
I play on a Minecraft 1.6 modded server on MyM, what will happen?
Mojang didn’t release the ability to change your name when this Minecraft version was available. This means that everything tied to your account is base on your Name and not your UUID. This means that items in your old username’s inventory, achievements, islands, baubles, claimblocks, claims, and all things regarding the market will be lost.
I play on a Minecraft 1.7 modded server on MyM, What will happen?
Most of the mods and plugins support UUIDs by this point. There are still mods that do not support UUIDS however. The affected things that you will probably need transferred are islands, Botania/Thaumcraft/Thermal Expansion data, and Questing Data.
I play on a Minecraft 1.10+ modded server on MyM, what will happen?
Even more mods/plugins support UUIDs. All that will really be lost is some mod related things like baubles, and botania. (I can’t think of anymore)
I am a Donor at MyM. What is going to happen to my premium rank, credits..?
Your rank and credits are automatically migrated as all of our plugins record your UUID and not your username, if it does not please open a ticket. I changed my Minecraft name but my name hasn’t updated on the forums? You have to manually tell the forums to update. Click the cog and click update username! There are very rare instances that this will not work. Open a forum support thread to have staff fix this.
What happens to the items that are specifically bound to my old name?
We can’t transfer these most of the time unfortunately.
In summary if you changed your name…
Patron Ranks & Legacy Tiers - Automatically transfers on all of our servers.
Skyblock Islands - All 1.7 Minecraft version and below will need to be transferred.
Claims - Will be lost on 1.6 servers (Request transfer).
Market - All items,history,etc will be lost on 1.7 and 1.6 servers (empty your market listings/history first).
Mod Items/Achievements/etc - 1.6 definitely lost, 1.7+ depends on mod/mod author.