diff --git a/api.go b/api.go
index 9ed065f..fc27e46 100644
--- a/api.go
+++ b/api.go
@@ -413,7 +413,17 @@ func (h *Headscale) handleMachineLogOut(
 		Str("machine", machine.Hostname).
 		Msg("Client requested logout")
 
-	h.ExpireMachine(&machine)
+	err := h.ExpireMachine(&machine)
+	if err != nil {
+		log.Error().
+			Caller().
+			Str("func", "handleMachineLogOut").
+			Err(err).
+			Msg("Failed to expire machine")
+		http.Error(writer, "Internal server error", http.StatusInternalServerError)
+
+		return
+	}
 
 	resp.AuthURL = ""
 	resp.MachineAuthorized = false
@@ -716,7 +726,16 @@ func (h *Headscale) handleAuthKey(
 
 		machine.NodeKey = nodeKey
 		machine.AuthKeyID = uint(pak.ID)
-		h.RefreshMachine(machine, registerRequest.Expiry)
+		err := h.RefreshMachine(machine, registerRequest.Expiry)
+		if err != nil {
+			log.Error().
+				Caller().
+				Str("machine", machine.Hostname).
+				Err(err).
+				Msg("Failed to refresh machine")
+
+			return
+		}
 	} else {
 		now := time.Now().UTC()
 
@@ -759,7 +778,18 @@ func (h *Headscale) handleAuthKey(
 		}
 	}
 
-	h.UsePreAuthKey(pak)
+	err = h.UsePreAuthKey(pak)
+	if err != nil {
+		log.Error().
+			Caller().
+			Err(err).
+			Msg("Failed to use pre-auth key")
+		machineRegistrations.WithLabelValues("new", RegisterMethodAuthKey, "error", pak.Namespace.Name).
+			Inc()
+		http.Error(writer, "Internal server error", http.StatusInternalServerError)
+
+		return
+	}
 
 	resp.MachineAuthorized = true
 	resp.User = *pak.Namespace.toUser()
diff --git a/machine_test.go b/machine_test.go
index 0287b0c..a06d0db 100644
--- a/machine_test.go
+++ b/machine_test.go
@@ -249,10 +249,12 @@ func (s *Suite) TestExpireMachine(c *check.C) {
 
 	machineFromDB, err := app.GetMachine("test", "testmachine")
 	c.Assert(err, check.IsNil)
+	c.Assert(machineFromDB, check.NotNil)
 
 	c.Assert(machineFromDB.isExpired(), check.Equals, false)
 
-	app.ExpireMachine(machineFromDB)
+	err = app.ExpireMachine(machineFromDB)
+	c.Assert(err, check.IsNil)
 
 	c.Assert(machineFromDB.isExpired(), check.Equals, true)
 }
diff --git a/oidc.go b/oidc.go
index 09365a4..8b5f024 100644
--- a/oidc.go
+++ b/oidc.go
@@ -345,7 +345,16 @@ func (h *Headscale) OIDCCallback(
 			Str("machine", machine.Hostname).
 			Msg("machine already registered, reauthenticating")
 
-		h.RefreshMachine(machine, time.Time{})
+		err := h.RefreshMachine(machine, time.Time{})
+		if err != nil {
+			log.Error().
+				Caller().
+				Err(err).
+				Msg("Failed to refresh machine")
+			http.Error(writer, "Failed to refresh machine", http.StatusInternalServerError)
+
+			return
+		}
 
 		var content bytes.Buffer
 		if err := oidcCallbackTemplate.Execute(&content, oidcCallbackTemplateConfig{
@@ -373,7 +382,7 @@ func (h *Headscale) OIDCCallback(
 
 		writer.Header().Set("Content-Type", "text/html; charset=utf-8")
 		writer.WriteHeader(http.StatusOK)
-		_, err := writer.Write(content.Bytes())
+		_, err = writer.Write(content.Bytes())
 		if err != nil {
 			log.Error().
 				Caller().