diff --git a/backend/00-router.go b/backend/00-router.go
index ec04817..13c0c42 100644
--- a/backend/00-router.go
+++ b/backend/00-router.go
@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"html"
+	"io"
 	"net/http"
 	"net/mail"
 	"net/url"
@@ -306,8 +307,10 @@ func emailBoxHandler(w http.ResponseWriter, r *http.Request) {
 	switch kind {
 	case "source":
 		if r.Header.Get("HX-Request") == "true" {
+			selected := selectedSourceAccount(accounts, r.URL.Query().Get("source"))
 			w.Header().Set("Content-Type", "text/html; charset=utf-8")
-			fmt.Fprint(w, renderEmailBoxSourcePane(accounts, r.URL.Query().Get("source")))
+			fmt.Fprint(w, renderEmailBoxSourcePane(accounts, selected.Name))
+			fmt.Fprintf(w, `<div id="list" hx-swap-oob="innerHTML">%s</div>`, renderInitialSourceMailboxList(selected))
 			return
 		}
 		renderSourceEmailBoxPage(w, r, accounts, r.URL.Query().Get("source"))
@@ -847,6 +850,7 @@ func renderTransferPage(w http.ResponseWriter, r *http.Request, mode transferMod
 
 func renderSourceEmailBoxPage(w http.ResponseWriter, r *http.Request, accounts []Account, selected string) {
 	user := CurrentUser(r)
+	selectedAccount := selectedSourceAccount(accounts, selected)
 	w.Header().Set("Content-Type", "text/html; charset=utf-8")
 	fmt.Fprintf(w, `<!doctype html><html lang="de"><head><meta charset="utf-8">
 <meta name="viewport" content="width=device-width,initial-scale=1">
@@ -879,12 +883,12 @@ func renderSourceEmailBoxPage(w http.ResponseWriter, r *http.Request, accounts [
 <div class="three-pane email-box-view">
   <aside class="pane pane-tree" id="source-tree">%s</aside>
   <div class="pane-resizer" data-resize-index="0"></div>
-  <section class="pane pane-list"><div class="pane-head">Nachrichten</div><div class="ef-empty">Quell-Postfach waehlen.</div></section>
+  <section class="pane pane-list" id="list">%s</section>
   <div class="pane-resizer" data-resize-index="1"></div>
   <section class="pane pane-read"><div class="ef-empty">Nachricht waehlen.</div></section>
 </div>
 <footer class="statusbar"><span id="mig-status" hx-get="/migrate/status" hx-trigger="load,every 3s" hx-swap="innerHTML">bereit</span></footer></body></html>`,
-		renderRibbonEmailBoxMenu("source"), renderRibbonTransferMenu(""), renderRibbonActions(false, user), renderEmailBoxSourcePane(accounts, selected))
+		renderRibbonEmailBoxMenu("source"), renderRibbonTransferMenu(""), renderRibbonActions(false, user), renderEmailBoxSourcePane(accounts, selectedAccount.Name), renderInitialSourceMailboxList(selectedAccount))
 }
 
 func renderTargetEmailBoxPage(w http.ResponseWriter, r *http.Request, accounts []Account) {
@@ -936,15 +940,7 @@ func renderEmailBoxSourcePane(accounts []Account, selected string) string {
 		b.WriteString(`<div class="pane-head archive-head"><span>Quell-Postfach</span></div><div class="ef-empty">Keine Quell-Postfaecher eingetragen.</div>`)
 		return b.String()
 	}
-	selectedAccount := sourceAccounts[0]
-	if selected != "" {
-		for _, a := range sourceAccounts {
-			if a.Name == selected {
-				selectedAccount = a
-				break
-			}
-		}
-	}
+	selectedAccount := selectedSourceAccount(accounts, selected)
 	b.WriteString(`<div class="pane-head archive-head"><span>Quell-Postfach</span><form class="archive-select-form" hx-get="/boxes/source" hx-target="#source-tree" hx-swap="innerHTML" hx-trigger="change from:#source-mailbox-select"><select id="source-mailbox-select" class="archive-select" name="source">`)
 	for _, a := range sourceAccounts {
 		label := fmt.Sprintf("%s (%s)", a.SrcUser, strings.ToUpper(accountProto(a)))
@@ -959,6 +955,21 @@ func renderEmailBoxSourcePane(accounts []Account, selected string) string {
 	return b.String()
 }
 
+func selectedSourceAccount(accounts []Account, selected string) Account {
+	sourceAccounts := accountsBySource(accounts)
+	if len(sourceAccounts) == 0 {
+		return Account{}
+	}
+	if selected != "" {
+		for _, a := range sourceAccounts {
+			if a.Name == selected {
+				return a
+			}
+		}
+	}
+	return sourceAccounts[0]
+}
+
 func renderSourceFolders(b *strings.Builder, account Account) {
 	fmt.Fprintf(b, `<div class="tree-node account">%s</div>`, html.EscapeString(account.SrcUser))
 	if accountProto(account) == "pop3" {
@@ -1003,7 +1014,48 @@ func fetchSourceFolderMessages(account Account, folder string) ([]RawMessage, er
 	return src.Fetch(folder)
 }
 
-func renderSourceMailboxMessageList(w http.ResponseWriter, account Account, folder string, messages []RawMessage) {
+func renderInitialSourceMailboxList(account Account) string {
+	if account.Name == "" {
+		return `<div class="pane-head">Nachrichten</div><div class="ef-empty">Quell-Postfach waehlen.</div>`
+	}
+	folder, err := firstSourceFolder(account)
+	if err != nil {
+		return fmt.Sprintf(`<div class="pane-head">Nachrichten</div><div class="ef-empty">%s</div>`, html.EscapeString(err.Error()))
+	}
+	messages, err := fetchSourceFolderMessages(account, folder)
+	if err != nil {
+		return fmt.Sprintf(`<div class="pane-head">Nachrichten</div><div class="ef-empty">%s</div>`, html.EscapeString(err.Error()))
+	}
+	var b strings.Builder
+	renderSourceMailboxMessageList(&b, account, folder, messages)
+	return b.String()
+}
+
+func firstSourceFolder(account Account) (string, error) {
+	if accountProto(account) == "pop3" {
+		return "INBOX", nil
+	}
+	src, err := OpenIMAPSource(account)
+	if err != nil {
+		return "", err
+	}
+	defer src.Close()
+	folders, err := src.Folders()
+	if err != nil {
+		return "", err
+	}
+	for _, folder := range folders {
+		if strings.EqualFold(folder.Name, "INBOX") {
+			return folder.Name, nil
+		}
+	}
+	if len(folders) == 0 {
+		return "", fmt.Errorf("Keine Ordner in diesem Quell-Postfach.")
+	}
+	return folders[0].Name, nil
+}
+
+func renderSourceMailboxMessageList(w io.Writer, account Account, folder string, messages []RawMessage) {
 	fmt.Fprintf(w, `<div class="pane-head">%s / %s (%d)</div>`, html.EscapeString(account.SrcUser), html.EscapeString(folder), len(messages))
 	for i, raw := range messages {
 		subject := "(ohne Betreff)"
