diff --git a/go.mod b/go.mod
index 1f06c01..00ce91e 100644
--- a/go.mod
+++ b/go.mod
@@ -27,6 +27,7 @@ require (
 	github.com/godbus/dbus/v5 v5.1.0 // indirect
 	github.com/nu7hatch/gouuid v0.0.0-20131221200532-179d4d0c4d8d // indirect
 	github.com/oxtoacart/bpool v0.0.0-20190530202638-03653db5a59c // indirect
+	github.com/rodolfoag/gow32 v0.0.0-20230512144032-1e896a3c51aa // indirect
 	github.com/tadvi/systray v0.0.0-20190226123456-11a2b8fa57af // indirect
 	golang.org/x/exp v0.0.0-20221208152030-732eee02a75a // indirect
 	golang.org/x/sys v0.15.0 // indirect
diff --git a/go.sum b/go.sum
index b853152..778bb6e 100644
--- a/go.sum
+++ b/go.sum
@@ -42,6 +42,8 @@ github.com/oxtoacart/bpool v0.0.0-20190530202638-03653db5a59c h1:rp5dCmg/yLR3mgF
 github.com/oxtoacart/bpool v0.0.0-20190530202638-03653db5a59c/go.mod h1:X07ZCGwUbLaax7L0S3Tw4hpejzu63ZrrQiUe6W0hcy0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/rodolfoag/gow32 v0.0.0-20230512144032-1e896a3c51aa h1:cd9mmDEXO4YxGYTbrhbfEt7btgUlcXFedTMoZ9fA4Ns=
+github.com/rodolfoag/gow32 v0.0.0-20230512144032-1e896a3c51aa/go.mod h1:w/ebPUfAcyZMYjstwPIWTEGSahChHx5R3Y+xElrvxDc=
 github.com/skratchdot/open-golang v0.0.0-20200116055534-eef842397966/go.mod h1:sUM3LWHvSMaG192sy56D9F7CNvL7jUJVXoqM1QKLnog=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
diff --git a/main.go b/main.go
index 46b6868..a02633a 100644
--- a/main.go
+++ b/main.go
@@ -11,14 +11,18 @@ import (
 	"os"
 	"runtime"
 	"sync/atomic"
+	"syscall"
 	"time"
 
 	"github.com/cornelk/hashmap"
 	"github.com/gen2brain/beeep"
 	"github.com/getlantern/systray"
 	"github.com/tawesoft/golib/v2/dialog"
+	"github.com/rodolfoag/gow32"
 )
 
+const MutexName = "proxmoxbackupclient_go"
+
 var defaultMailSubjectTemplate = "Backup {{.Status}}"
 var defaultMailBodyTemplate = `{{if .Success}}Backup complete ({{.FromattedDuration}})
 Chunks New {{.NewChunks}}, Reused {{.ReusedChunks}}.{{else}}Error occurred while working, backup may be not completed.
@@ -75,6 +79,16 @@ func main() {
 	}
 
 	if runtime.GOOS == "windows" {
+		mutexid, err := gow32.CreateMutex(MutexName)
+		if (err != nil) {
+			if exitcode := int(err.(syscall.Errno)); exitcode == gow32.ERROR_ALREADY_EXISTS {
+				dialog.Error("Backup jobs need to run exclusively, please wait until the previous job has finished")
+				os.Exit(2)
+			}
+			// this should never happen
+			panic(err)
+		}
+		defer gow32.ReleaseMutex(mutexid)
 
 		go systray.Run(func() {
 			systray.SetIcon(ICON)