diff --git a/actions/challengeRegistration.js b/actions/challengeRegistration.js
index 8f73c9020..791121d3f 100644
--- a/actions/challengeRegistration.js
+++ b/actions/challengeRegistration.js
@@ -869,9 +869,12 @@ exports.registerChallenge = {
                 if (error) {
                     console.log("error: " +  error);
                     cb(error);
-                } else {
-                    console.log("error11: " +  error);
-                    api.dataAccess.executeQuery('check_challenge_exists', {challengeId: challengeId}, connection.dbConnectionMap, cb);
+                } else {                   
+                    api.helper.checkUserActivated(connection.caller.handle, api, connection.dbConnectionMap, function (err, inactive) {
+                        var fail = err || inactive;
+                        if (fail) cb(fail);
+                        else api.dataAccess.executeQuery('check_challenge_exists', {challengeId: challengeId}, connection.dbConnectionMap, cb);
+                    }, "You must activate your account in order to participate. Please check your e-mail in order to complete the activation process, or contact support@topcoder.com if you did not receive an e-mail.");                    
                 }
             }, function (result, cb) {
                 if (result.length > 0) {
diff --git a/actions/challenges.js b/actions/challenges.js
index e03414f49..88fb6b460 100755
--- a/actions/challenges.js
+++ b/actions/challenges.js
@@ -125,7 +125,9 @@ var QUERY_PATH = './queries/';
  */
 var TECHNOLOGY_FILTER = ' AND EXISTS (SELECT DISTINCT 1 FROM comp_technology ct WHERE ct.comp_vers_id = pi1.value ' +
     'AND ct.technology_type_id IN (@filter@))';
-
+    
+var EXT_TECHNOLOGY_FILTER = ' AND (pn.value LIKE ("%@tech@%") OR EXISTS (SELECT DISTINCT 1 FROM comp_technology ct WHERE ct.comp_vers_id = pi1.value ' +
+    'AND ct.technology_type_id IN (@filter@)))';
 /**
  * The platform filter for challenges api.
  * @since 1.23
@@ -745,7 +747,7 @@ function transferResultV2(src, helper) {
  * @param {String} content - the content that need in template.
  * @since 1.23
  */
-var editSql = function (sql, template, content) {
+var editSql = function (sql, template, content, tech) {
     // For empty sql just return it.
     if (sql.length === 0) {
         return sql;
@@ -753,6 +755,7 @@ var editSql = function (sql, template, content) {
     var index = sql.toLowerCase().indexOf('order by');
     if (!_.isUndefined(template)) {
         template = template.replace('@filter@', content);
+        template = template.replace('@tech@', tech);
     }
     return sql.slice(0, index) + template + sql.slice(index, sql.length);
 };
@@ -776,8 +779,13 @@ var addFilter = function (sql, filter, isMyChallenges, helper, caller) {
 
     if (_.isDefined(filter.technologies)) {
         technology = filter.technologies.join(', ');
-        sql.count = editSql(sql.count, TECHNOLOGY_FILTER, technology);
-        sql.data = editSql(sql.data, TECHNOLOGY_FILTER, technology);
+        if (filter.tech) {
+            sql.count = editSql(sql.count, EXT_TECHNOLOGY_FILTER, technology, filter.tech);
+            sql.data = editSql(sql.data, EXT_TECHNOLOGY_FILTER, technology, filter.tech);            
+        } else {
+            sql.count = editSql(sql.count, TECHNOLOGY_FILTER, technology);
+            sql.data = editSql(sql.data, TECHNOLOGY_FILTER, technology);
+        }
     }
 
     if (_.isDefined(filter.challengeType)) {
@@ -3708,6 +3716,10 @@ var getChallenges = function (api, connection, listType, isMyChallenges, next) {
         },
         function (cb) {
             validateInputParameterV2(helper, caller, type, query, filter, pageIndex, pageSize, sortColumn, sortOrder, listType, dbConnectionMap, cb);
+            
+            if (filter.technologies) {
+                filter.tech = filter.technologies.split(',')[0];
+            }
         }, function (cb) {
             if (pageIndex === -1) {
                 pageIndex = 1;
diff --git a/apiary.apib b/apiary.apib
index 955a88fc9..f7dd6dcd6 100644
--- a/apiary.apib
+++ b/apiary.apib
@@ -9946,7 +9946,7 @@ Request
         }
 
 ## Register for a software/studio challenge [/challenges/{challengeId}/register]
-### Register for a software/studio challenge [GET]
+### Register for a software/studio challenge [POST]
 
 + Parameters
     + challengeId (required, number, `1234567`) ... The challenge for which to register
diff --git a/initializers/helper.js b/initializers/helper.js
index 466d970b1..198a9f05d 100644
--- a/initializers/helper.js
+++ b/initializers/helper.js
@@ -1625,7 +1625,7 @@ helper.checkUserExists = function (handle, api, dbConnectionMap, callback) {
  * @param {Object} dbConnectionMap - the database connection map
  * @param {Function<err>} callback - the callback function
  */
-helper.checkUserActivated = function (handle, api, dbConnectionMap, callback) {
+helper.checkUserActivated = function (handle, api, dbConnectionMap, callback, textResponse) {
     api.dataAccess.executeQuery('check_user_activated', { handle: handle }, dbConnectionMap, function (err, result) {
         if (err) {
             callback(err, null);
@@ -1634,7 +1634,8 @@ helper.checkUserActivated = function (handle, api, dbConnectionMap, callback) {
         if (result && result[0] && result[0].status === 'A') {
             callback(err, null);
         } else {
-            callback(err, new BadRequestError('User is not activated.'));
+            var message = textResponse || 'User is not activated.';
+            callback(err, new BadRequestError(message));
         }
     });
 };