diff --git a/routers/install/install.go b/routers/install/install.go
index 8466caa2bf5..b0357c77203 100644
--- a/routers/install/install.go
+++ b/routers/install/install.go
@@ -312,8 +312,10 @@ func SubmitInstall(ctx *context.Context) {
 		return
 	}
 
-	// Save settings.
+	// Some logic also depends on the config values, so EnvironmentToConfig should also be applied first.
+	// EnvironmentToConfig is applied on each start up, so it also must override the "install form", so it must be applied after (twice).
 	cfg, err := setting.NewConfigProviderFromFile(setting.CustomConf)
+	setting.EnvironmentToConfig(cfg, os.Environ())
 	if err != nil {
 		log.Error("Failed to load custom conf '%s': %v", setting.CustomConf, err)
 	}