diff --git a/rhodecode/lib/dbmigrate/schema/db_1_4_0.py b/rhodecode/lib/dbmigrate/schema/db_1_4_0.py
--- a/rhodecode/lib/dbmigrate/schema/db_1_4_0.py
+++ b/rhodecode/lib/dbmigrate/schema/db_1_4_0.py
@@ -787,7 +787,7 @@ class Repository(Base, BaseModel):
         from rhodecode.lib.vcs.backends.git import GitRepository
         required = (MercurialRepository, GitRepository)
         if not isinstance(repo, required):
-            raise Exception('repo must be instance of %s' % required)
+            raise Exception('repo must be instance of %s' % (','.join(required)))
 
         # inject ui extra param to log this action via push logger
         for k, v in extras.items():
diff --git a/rhodecode/lib/dbmigrate/schema/db_1_5_0.py b/rhodecode/lib/dbmigrate/schema/db_1_5_0.py
--- a/rhodecode/lib/dbmigrate/schema/db_1_5_0.py
+++ b/rhodecode/lib/dbmigrate/schema/db_1_5_0.py
@@ -807,7 +807,7 @@ class Repository(Base, BaseModel):
         from rhodecode.lib.vcs.backends.git import GitRepository
         required = (MercurialRepository, GitRepository)
         if not isinstance(repo, required):
-            raise Exception('repo must be instance of %s' % required)
+            raise Exception('repo must be instance of %s' % (','.join(required)))
 
         # inject ui extra param to log this action via push logger
         for k, v in extras.items():
diff --git a/rhodecode/lib/dbmigrate/schema/db_1_5_2.py b/rhodecode/lib/dbmigrate/schema/db_1_5_2.py
--- a/rhodecode/lib/dbmigrate/schema/db_1_5_2.py
+++ b/rhodecode/lib/dbmigrate/schema/db_1_5_2.py
@@ -873,7 +873,7 @@ class Repository(Base, BaseModel):
         from rhodecode.lib.vcs.backends.git import GitRepository
         required = (MercurialRepository, GitRepository)
         if not isinstance(repo, required):
-            raise Exception('repo must be instance of %s' % required)
+            raise Exception('repo must be instance of %s' % (','.join(required)))
 
         # inject ui extra param to log this action via push logger
         for k, v in extras.items():