diff --git a/src/controllers/api/account/emailChangeRequestController.js b/src/controllers/api/account/emailChangeRequestController.js
index 1b82d74..4791ba2 100644
--- a/src/controllers/api/account/emailChangeRequestController.js
+++ b/src/controllers/api/account/emailChangeRequestController.js
@@ -43,7 +43,7 @@ module.exports.post = async function(req, res){
 
             //Check to make sure the user is logged in
             if(req.session.user == null){
-                errorHandler(res, "Invalid user!");
+                return errorHandler(res, "Invalid user!");
             }
 
             //Authenticate and find user model from DB
@@ -51,11 +51,22 @@ module.exports.post = async function(req, res){
 
             //If we have an invalid user
             if(userDB == null){
-                errorHandler(res, "Invalid user!");
+                return errorHandler(res, "Invalid user!");
             }
 
             if(userDB.email == email){
-                errorHandler(res, "Cannot set current email!");
+                return errorHandler(res, "Cannot set current email!");
+            }
+
+
+            //Look through DB and migration cache for existing email
+            const existingDB = await userModel.findOne({email: new RegExp(email, 'i')});
+            const needsMigration = userModel.migrationCache.emails.includes(email.toLowerCase());
+
+            //If the email is in use
+            if(existingDB != null || needsMigration){
+                //Complain
+                return errorHandler(res, "Email already in use!");
             }
 
             //Generate the password reset link
diff --git a/src/schemas/user/migrationSchema.js b/src/schemas/user/migrationSchema.js
index b03b1dc..2856094 100644
--- a/src/schemas/user/migrationSchema.js
+++ b/src/schemas/user/migrationSchema.js
@@ -27,7 +27,6 @@ const permissionModel = require('../permissionSchema');
 const tokeModel = require('../tokebot/tokeSchema');
 const loggerUtils = require('../../utils/loggerUtils');
 
-
 /**
  * DB Schema for documents representing legacy fore.st migration data for a single user account
  */
@@ -208,7 +207,7 @@ migrationSchema.statics.ingestLegacyUser = async function(rawProfile){
         //If we found the user in the database
         if(foundMigration != null || foundUser != null){
             //Scream
-            //loggerUtils.consoleWarn(`Found legacy user ${profileArray[1]} in database, skipping migration!`);
+            loggerUtils.consoleWarn(`Found legacy user ${profileArray[1]} in database, skipping migration!`);
             //BAIL!
             return;
         }
@@ -292,4 +291,31 @@ migrationSchema.statics.ingestTokeMaps = async function(rawTokeMaps){
     }
 }
 
+migrationSchema.statics.buildMigrationCache = async function(){
+    //Pull all profiles from the Legacy Profile Migration DB collection
+    const legacyProfiles = await this.find();
+
+    //For each profile in the migration collection
+    for(const profile of legacyProfiles){
+        //Push the username into the migration cache
+        userModel.migrationCache.users.push(profile.user.toLowerCase());
+        //If the profile has an email address set
+        if(profile.email != null && profile.email != ''){
+            //Add the email to the migration cache
+            userModel.migrationCache.emails.push(profile.email.toLowerCase());
+        }
+    }
+}
+
+//Methods
+/**
+ * Consumes a migration profile and creates a new, modern canopy profile from the original.
+ * @param {String} oldPass - Original password to authenticate migration against
+ * @param {String} newPass - New password to re-hash with modern hashing algo
+ * @param {String} confirmPass - Confirmation for the new pass
+ */
+migrationSchema.methods.consume = async function(oldPass, newPass, confirmPass){
+
+}
+
 module.exports = mongoose.model("migration", migrationSchema);
\ No newline at end of file
diff --git a/src/schemas/user/userSchema.js b/src/schemas/user/userSchema.js
index dd13b24..003f2e6 100644
--- a/src/schemas/user/userSchema.js
+++ b/src/schemas/user/userSchema.js
@@ -226,6 +226,18 @@ userSchema.post('deleteOne', {document: true}, async function (){
 });
 
 //statics
+/**
+ * Holds cache of usernames of profiles stored in the Legacy Profile Migration collection
+ * 
+ * We can't directly reference migrationSchema, as it would cause a circular reference
+ * To deal with this, migration schema caches it's regestered users into this array on startup.
+ * Bonus pts for improved performance on registration calls
+ */
+userSchema.statics.migrationCache = {
+    users: [],
+    emails: []
+};
+
 /**
  * Registers a new user account with given information
  * @param {Object} userObj - Object representing user to register, generated by the client
@@ -237,11 +249,31 @@ userSchema.statics.register = async function(userObj, ip){
 
     //Check password confirmation matches
     if(pass == passConfirm){
+        //Setup user query
+        let userQuery = {user: new RegExp(user, 'i')};
+
+        //If we have an email
+        if(email != null && email != ""){
+            userQuery = {$or: [
+                userQuery,
+                {email: new RegExp(email, 'i')}
+            ]};
+        }
+
         //Look for a user (case insensitive)
-        var userDB = await this.findOne({user: new RegExp(user, 'i')}); 
+        var userDB = await this.findOne(userQuery); 
+
+        //Look for a legacy profile
+        let needsMigration = this.migrationCache.users.includes(user.toLowerCase());
+
+        //If the email isn't null and we didnt hit a migration username
+        if(email != null && !needsMigration){
+            //Check for migration email
+            needsMigration = this.migrationCache.emails.includes(email.toLowerCase());
+        }
 
         //If the user is found or someones trying to impersonate tokeboi
-        if(userDB || user.toLowerCase() == "tokebot"){
+        if(userDB || needsMigration || user.toLowerCase() == "tokebot"){
             throw loggerUtils.exceptionSmith("User name/email already taken!", "validation");
         }else{
             //Increment the user count, pulling the id to tattoo to the user
diff --git a/src/server.js b/src/server.js
index c1b2e2f..333dfc3 100644
--- a/src/server.js
+++ b/src/server.js
@@ -195,6 +195,9 @@ async function asyncKickStart(){
     //Run legacy migration
     await migrationModel.ingestLegacyDump();
 
+    //Build migration cache
+    await migrationModel.buildMigrationCache();
+
     //Calculate Toke Map
     await tokeModel.calculateTokeMap();