diff --git a/autodiscover/autodiscover.go b/autodiscover/autodiscover.go
index 23c4401..4e081db 100644
--- a/autodiscover/autodiscover.go
+++ b/autodiscover/autodiscover.go
@@ -295,7 +295,7 @@ func autodiscover(domain string, mapi bool) (*utils.AutodiscoverResp, string, er
 
 	req, err := http.NewRequest("POST", autodiscoverURL, strings.NewReader(r))
 	req.Header.Add("Content-Type", "text/xml")
-	req.Header.Add("User-Agent", "ruler")
+	req.Header.Add("User-Agent", SessionConfig.UserAgent)
 
 	if mapi == true {
 		req.Header.Add("X-MapiHttpCapability", "1")            //we want MAPI info
@@ -453,7 +453,7 @@ func (l InsecureRedirectsO365) RoundTrip(req *http.Request) (resp *http.Response
 
 		req, err = http.NewRequest("POST", URL.String(), strings.NewReader(r))
 		req.Header.Add("Content-Type", "text/xml")
-		req.Header.Add("User-Agent", "ruler")
+		req.Header.Add("User-Agent", SessionConfig.UserAgent)
 
 		req.Header.Add("X-MapiHttpCapability", "1") //we want MAPI info
 		req.Header.Add("X-AnchorMailbox", l.User)   //we want MAPI info
diff --git a/autodiscover/brute.go b/autodiscover/brute.go
index 76e249e..5c6c455 100644
--- a/autodiscover/brute.go
+++ b/autodiscover/brute.go
@@ -37,6 +37,7 @@ var verbose = false
 var insecure = false
 var stopSuccess = false
 var proxyURL string
+var userAgent string
 var user_as_pass = true
 
 func autodiscoverDomain(domain string) string {
@@ -74,6 +75,7 @@ func autodiscoverDomain(domain string) string {
 
 	req, err := http.NewRequest("GET", autodiscoverURL, nil)
 	req.Header.Add("Content-Type", "text/xml")
+	req.Header.Add("User-Agent", userAgent)
 
 	tr := &http.Transport{
 		TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
@@ -113,7 +115,7 @@ func autodiscoverDomain(domain string) string {
 }
 
 //Init function to setup the brute-force session
-func Init(domain, usersFile, passwordsFile, userpassFile, pURL string, b, i, s, v bool, c, d, t int) error {
+func Init(domain, usersFile, passwordsFile, userpassFile, pURL, u string, b, i, s, v bool, c, d, t int) error {
 	stopSuccess = s
 	insecure = i
 	basic = b
@@ -122,6 +124,7 @@ func Init(domain, usersFile, passwordsFile, userpassFile, pURL string, b, i, s,
 	consc = c
 	concurrency = t
 	proxyURL = pURL
+	userAgent = u
 
 	autodiscoverURL = autodiscoverDomain(domain)
 
@@ -332,7 +335,7 @@ func connect(autodiscoverURL, user, password string, basic, insecure bool) Resul
 		proxy, err := url.Parse(proxyURL)
 		if err != nil {
 			result.Error = err
-			return result 
+			return result
 		}
 		tr = &http.Transport{Proxy: http.ProxyURL(proxy),
 			TLSClientConfig: &tls.Config{InsecureSkipVerify: true},
@@ -357,6 +360,7 @@ func connect(autodiscoverURL, user, password string, basic, insecure bool) Resul
 
 	req, err := http.NewRequest("GET", autodiscoverURL, nil)
 	req.Header.Add("Content-Type", "text/xml")
+	req.Header.Add("User-Agent", userAgent)
 
 	//if basic authi is required, set auth header
 	if basic == true {
diff --git a/http-ntlm/ntlmtransport.go b/http-ntlm/ntlmtransport.go
index d57dc77..ee178a0 100644
--- a/http-ntlm/ntlmtransport.go
+++ b/http-ntlm/ntlmtransport.go
@@ -53,7 +53,8 @@ func (t NtlmTransport) RoundTrip(req *http.Request) (res *http.Response, err err
 	b, _ := session.GenerateNegotiateMessage()
 	// first send NTLM Negotiate header
 	r, _ := http.NewRequest("GET", req.URL.String(), strings.NewReader(""))
-	r.Header.Add("Authorization", "NTLM "+utils.EncBase64(b.Bytes()))
+	r.Header.Add("Authorization", "NTLM " + utils.EncBase64(b.Bytes()))
+	r.Header.Add("User-Agent", req.UserAgent())
 
 	if t.Proxy == "" {
 		Transport = http.Transport{
@@ -125,10 +126,9 @@ func (t NtlmTransport) RoundTrip(req *http.Request) (res *http.Response, err err
 		}
 
 		// set NTLM Authorization header
-		req.Header.Set("Authorization", "NTLM "+utils.EncBase64(authenticate.Bytes()))
+		req.Header.Set("Authorization", "NTLM " + utils.EncBase64(authenticate.Bytes()))
 
 		resp, err = client.Do(req)
-    
 	}
 	return resp, err
 }
diff --git a/mapi/mapi.go b/mapi/mapi.go
index 20f9c66..866470f 100644
--- a/mapi/mapi.go
+++ b/mapi/mapi.go
@@ -176,6 +176,7 @@ func mapiRequestHTTP(URL, mapiType string, body []byte) ([]byte, error) {
 
 	req, err := http.NewRequest("POST", URL, bytes.NewReader(body))
 	addMapiHeaders(req, mapiType)
+	req.Header.Add("User-Agent", AuthSession.UserAgent)
 	req.SetBasicAuth(AuthSession.Email, AuthSession.Pass)
 
 	req.Close = true
diff --git a/ruler.go b/ruler.go
index 8d73cfc..992551c 100644
--- a/ruler.go
+++ b/ruler.go
@@ -92,6 +92,7 @@ func discover(c *cli.Context) error {
 	config.RPCEncrypt = !c.GlobalBool("noencrypt")
 	config.CookieJar, _ = cookiejar.New(nil)
 	config.Proxy = c.GlobalString("proxy")
+	config.UserAgent = c.GlobalString("useragent")
 	url := c.GlobalString("url")
 
 	if url == "" {
@@ -164,7 +165,7 @@ func brute(c *cli.Context) error {
 	if c.GlobalBool("o365") == true {
 		domain = "https://autodiscover-s.outlook.com/autodiscover/autodiscover.xml"
 	}
-	if e := autodiscover.Init(domain, c.String("users"), c.String("passwords"), c.String("userpass"), c.GlobalString("proxy"), c.GlobalBool("basic"), c.GlobalBool("insecure"), c.Bool("stop"), c.Bool("verbose"), c.Int("attempts"), c.Int("delay"), c.Int("threads")); e != nil {
+	if e := autodiscover.Init(domain, c.String("users"), c.String("passwords"), c.String("userpass"), c.GlobalString("proxy"), c.GlobalString("useragent"), c.GlobalBool("basic"), c.GlobalBool("insecure"), c.Bool("stop"), c.Bool("verbose"), c.Int("attempts"), c.Int("delay"), c.Int("threads")); e != nil {
 		return e
 	}
 
@@ -313,6 +314,7 @@ func connect(c *cli.Context) error {
 	config.RPCEncrypt = !c.GlobalBool("noencrypt")
 	config.CookieJar, _ = cookiejar.New(nil)
 	config.Proxy = c.GlobalString("proxy")
+	config.UserAgent = c.GlobalString("useragent")
 	//add supplied cookie to the cookie jar
 	if c.GlobalString("cookie") != "" {
 		//split into cookies and then into name : value
@@ -1189,6 +1191,11 @@ A tool by @_staaldraad from @sensepost to abuse Exchange Services.`
 			Value: "",
 			Usage: "If you need to use an upstream proxy. Works with https://user:pass@ip:port or https://ip:port",
 		},
+		cli.StringFlag{
+			Name:  "useragent",
+			Value: "ruler",
+			Usage: "Custom User-Agent string",
+		},
 		cli.BoolFlag{
 			Name:  "insecure,k",
 			Usage: "Ignore server SSL certificate errors",
diff --git a/utils/datatypes.go b/utils/datatypes.go
index fadaf1a..7da41cf 100644
--- a/utils/datatypes.go
+++ b/utils/datatypes.go
@@ -9,15 +9,16 @@ import (
 
 //Config containing the session variables
 type Config struct {
-	Domain   string
-	User     string
-	Pass     string
-	Email    string
-	Basic    bool
-	Insecure bool
-	Verbose  bool
-	Admin    bool
-	Proxy    string
+	Domain    string
+	User      string
+	Pass      string
+	Email     string
+	Basic     bool
+	Insecure  bool
+	Verbose   bool
+	Admin     bool
+	Proxy     string
+	UserAgent string
 }
 
 //Session stores authentication cookies ect
@@ -27,6 +28,7 @@ type Session struct {
 	Email         string
 	Domain        string
 	Proxy         string
+	UserAgent     string
 	Basic         bool
 	Insecure      bool
 	Verbose       bool