diff --git a/pkg/service/v0/validator.go b/pkg/service/v0/validator.go
index 2ef5202fc0..71f426c617 100644
--- a/pkg/service/v0/validator.go
+++ b/pkg/service/v0/validator.go
@@ -5,6 +5,7 @@ import (
 
 	validation "github.com/go-ozzo/ozzo-validation/v4"
 	"github.com/go-ozzo/ozzo-validation/v4/is"
+	merrors "github.com/micro/go-micro/v2/errors"
 	"github.com/owncloud/ocis-settings/pkg/proto/v0"
 )
 
@@ -32,43 +33,49 @@ func validateSaveBundle(req *proto.SaveBundleRequest) error {
 		validation.Field(&req.Bundle.DisplayName, validation.Required),
 		validation.Field(&req.Bundle.Settings, validation.Required),
 	); err != nil {
-		return err
+		return merrors.FromError(err)
 	}
 	if err := validateResource(req.Bundle.Resource); err != nil {
-		return err
+		return merrors.FromError(err)
 	}
 	for i := range req.Bundle.Settings {
 		if err := validateSetting(req.Bundle.Settings[i]); err != nil {
-			return err
+			return merrors.FromError(err)
 		}
 	}
 	return nil
 }
 
 func validateGetBundle(req *proto.GetBundleRequest) error {
-	return validation.Validate(&req.BundleId, requireAccountID...)
+	if err := validation.Validate(&req.BundleId, requireAccountID...); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }
 
 func validateListBundles(req *proto.ListBundlesRequest) error {
-	return validation.Validate(&req.AccountUuid, requireAccountID...)
+	if err := validation.Validate(&req.AccountUuid, requireAccountID...); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }
 
 func validateAddSettingToBundle(req *proto.AddSettingToBundleRequest) error {
-	if err := validation.ValidateStruct(
-		req,
-		validation.Field(&req.BundleId, is.UUID),
-	); err != nil {
-		return err
+	if err := validation.ValidateStruct(req, validation.Field(&req.BundleId, is.UUID)); err != nil {
+		return merrors.FromError(err)
 	}
 	return validateSetting(req.Setting)
 }
 
 func validateRemoveSettingFromBundle(req *proto.RemoveSettingFromBundleRequest) error {
-	return validation.ValidateStruct(
+	if err := validation.ValidateStruct(
 		req,
 		validation.Field(&req.BundleId, is.UUID),
 		validation.Field(&req.SettingId, is.UUID),
-	)
+	); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }
 
 func validateSaveValue(req *proto.SaveValueRequest) error {
@@ -79,11 +86,11 @@ func validateSaveValue(req *proto.SaveValueRequest) error {
 		validation.Field(&req.Value.SettingId, is.UUID),
 		validation.Field(&req.Value.AccountUuid, requireAccountID...),
 	); err != nil {
-		return err
+		return merrors.FromError(err)
 	}
 
 	if err := validateResource(req.Value.Resource); err != nil {
-		return err
+		return merrors.FromError(err)
 	}
 
 	// TODO: validate values against the respective setting. need to check if constraints of the setting are fulfilled.
@@ -91,46 +98,67 @@ func validateSaveValue(req *proto.SaveValueRequest) error {
 }
 
 func validateGetValue(req *proto.GetValueRequest) error {
-	return validation.Validate(req.Id, is.UUID)
+	if err := validation.Validate(req.Id, is.UUID); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }
 
 func validateListValues(req *proto.ListValuesRequest) error {
-	return validation.ValidateStruct(
+	if err := validation.ValidateStruct(
 		req,
 		validation.Field(&req.BundleId, validation.When(req.BundleId != "", is.UUID)),
 		validation.Field(&req.AccountUuid, validation.When(req.AccountUuid != "", validation.Match(regexForAccountUUID))),
-	)
+	); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }
 
 func validateListRoles(req *proto.ListBundlesRequest) error {
-	return validation.Validate(&req.AccountUuid, requireAccountID...)
+	if err := validation.Validate(&req.AccountUuid, requireAccountID...); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }
 
 func validateListRoleAssignments(req *proto.ListRoleAssignmentsRequest) error {
-	return validation.Validate(req.AccountUuid, requireAccountID...)
+	if err := validation.Validate(req.AccountUuid, requireAccountID...); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }
 
 func validateAssignRoleToUser(req *proto.AssignRoleToUserRequest) error {
-	return validation.ValidateStruct(
+	if err := validation.ValidateStruct(
 		req,
 		validation.Field(&req.AccountUuid, requireAccountID...),
 		validation.Field(&req.RoleId, is.UUID),
-	)
+	); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }
 
 func validateRemoveRoleFromUser(req *proto.RemoveRoleFromUserRequest) error {
-	return validation.ValidateStruct(
+	if err := validation.ValidateStruct(
 		req,
 		validation.Field(&req.Id, is.UUID),
-	)
+	); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }
 
 // validateResource is an internal helper for validating the content of a resource.
 func validateResource(resource *proto.Resource) error {
 	if err := validation.Validate(&resource, validation.Required); err != nil {
-		return err
+		return merrors.FromError(err)
 	}
-	return validation.Validate(&resource, validation.NotIn(proto.Resource_TYPE_UNKNOWN))
+	if err := validation.Validate(&resource, validation.NotIn(proto.Resource_TYPE_UNKNOWN)); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }
 
 // validateSetting is an internal helper for validating the content of a setting.
@@ -141,7 +169,10 @@ func validateSetting(setting *proto.Setting) error {
 		validation.Field(&setting.Id, validation.When(setting.Id != "", is.UUID)),
 		validation.Field(&setting.Name, requireAlphanumeric...),
 	); err != nil {
-		return err
+		return merrors.FromError(err)
 	}
-	return validateResource(setting.Resource)
+	if err := validateResource(setting.Resource); err != nil {
+		return merrors.FromError(err)
+	}
+	return nil
 }