diff --git a/models/user/user.go b/models/user/user.go
index d7331d79f0b09..e805d7485f91f 100644
--- a/models/user/user.go
+++ b/models/user/user.go
@@ -831,6 +831,18 @@ type CountUserFilter struct {
 	IsActive       optional.Option[bool]
 }
 
+// HasUsers returns true if any user exists in the database.
+// It performs a much more efficient check than counting all users.
+func HasUsers(ctx context.Context) (bool, error) {
+	sess := db.GetEngine(ctx)
+	exists, err := sess.Exist(new(User))
+	if err != nil {
+		return false, fmt.Errorf("error checking user existence: %w", err)
+	}
+
+	return exists, nil
+}
+
 // CountUsers returns number of users.
 func CountUsers(ctx context.Context, opts *CountUserFilter) int64 {
 	return countUsers(ctx, opts)
diff --git a/options/locale/locale_en-US.ini b/options/locale/locale_en-US.ini
index 4384ebc3d7541..8ff98e16c78eb 100644
--- a/options/locale/locale_en-US.ini
+++ b/options/locale/locale_en-US.ini
@@ -421,6 +421,7 @@ remember_me.compromised = The login token is not valid anymore which may indicat
 forgot_password_title= Forgot Password
 forgot_password = Forgot password?
 need_account = Need an account?
+sign_up_tip = You are registering the first account in the system. Please carefully remember your username and password, as losing this information could cause significant inconvenience later.
 sign_up_now = Register now.
 sign_up_successful = Account was successfully created. Welcome!
 confirmation_mail_sent_prompt_ex = A new confirmation email has been sent to <b>%s</b>. Please check your inbox within the next %s to complete the registration process. If your registration email address is incorrect, you can sign in again and change it.
diff --git a/routers/install/install.go b/routers/install/install.go
index 2962f3948fea1..68f402b210dd7 100644
--- a/routers/install/install.go
+++ b/routers/install/install.go
@@ -607,5 +607,7 @@ func SubmitInstall(ctx *context.Context) {
 // InstallDone shows the "post-install" page, makes it easier to develop the page.
 // The name is not called as "PostInstall" to avoid misinterpretation as a handler for "POST /install"
 func InstallDone(ctx *context.Context) { //nolint
+	hasUsers, _ := user_model.HasUsers(ctx)
+	ctx.Data["IsAccountCreated"] = hasUsers
 	ctx.HTML(http.StatusOK, tplPostInstall)
 }
diff --git a/routers/web/auth/auth.go b/routers/web/auth/auth.go
index 69b9d285b78cc..bb9bb66f49ed0 100644
--- a/routers/web/auth/auth.go
+++ b/routers/web/auth/auth.go
@@ -424,6 +424,10 @@ func SignUp(ctx *context.Context) {
 
 	ctx.Data["SignUpLink"] = setting.AppSubURL + "/user/sign_up"
 
+	hasUsers, _ := user_model.HasUsers(ctx)
+
+	ctx.Data["IsFirstTimeRegistration"] = !hasUsers
+
 	oauth2Providers, err := oauth2.GetOAuth2Providers(ctx, optional.Some(true))
 	if err != nil {
 		ctx.ServerError("UserSignUp", err)
diff --git a/templates/post-install.tmpl b/templates/post-install.tmpl
index 0c9aa35c9093a..44099ce29d5d0 100644
--- a/templates/post-install.tmpl
+++ b/templates/post-install.tmpl
@@ -4,7 +4,7 @@
 		<!-- the "cup" has a handler, so move it a little leftward to make it visually in the center -->
 		<div class="tw-ml-[-30px]"><img width="160" src="{{AssetUrlPrefix}}/img/loading.png" alt aria-hidden="true"></div>
 		<div class="tw-my-[2em] tw-text-[18px]">
-			<a id="goto-user-login" href="{{AppSubUrl}}/user/login">{{ctx.Locale.Tr "install.installing_desc"}}</a>
+			<a id="goto-signup-or-signin" href="{{AppSubUrl}}{{if .IsAccountCreated}}/user/login{{else}}/user/sign_up{{end}}">{{ctx.Locale.Tr "install.installing_desc"}}</a>
 		</div>
 	</div>
 </div>
diff --git a/templates/user/auth/signup_inner.tmpl b/templates/user/auth/signup_inner.tmpl
index d66568199dd8d..a3f6e1471f8d8 100644
--- a/templates/user/auth/signup_inner.tmpl
+++ b/templates/user/auth/signup_inner.tmpl
@@ -7,6 +7,9 @@
 		{{end}}
 	</h4>
 	<div class="ui attached segment">
+		{{if .IsFirstTimeRegistration}}
+			<p>{{ctx.Locale.Tr "auth.sign_up_tip"}}</p>
+		{{end}}
 		<form class="ui form" action="{{.SignUpLink}}" method="post">
 			{{.CsrfTokenHtml}}
 			{{if or (not .LinkAccountMode) (and .LinkAccountMode .LinkAccountModeRegister)}}
diff --git a/web_src/js/features/install.ts b/web_src/js/features/install.ts
index 34df4757f9f80..bd8e57265c846 100644
--- a/web_src/js/features/install.ts
+++ b/web_src/js/features/install.ts
@@ -104,7 +104,7 @@ function initPreInstall() {
 }
 
 function initPostInstall() {
-  const el = document.querySelector('#goto-user-login');
+  const el = document.querySelector('#goto-signup-or-signin');
   if (!el) return;
 
   const targetUrl = el.getAttribute('href');