diff --git a/src/components/manifest/ManifestForm.jsx b/src/components/manifest/ManifestForm.jsx
index d530ef5..8cce2fe 100644
--- a/src/components/manifest/ManifestForm.jsx
+++ b/src/components/manifest/ManifestForm.jsx
@@ -868,6 +868,7 @@ class ManifestForm extends PureComponent {
 
   handleRemoveAllLines() {
     this.setState((prev) => {
+      let nextLines = [];
       if (this.props.kind === 'order') {
         const shippedSkus = new Set();
         for (const sh of prev.shipments || []) {
@@ -876,7 +877,7 @@ class ManifestForm extends PureComponent {
           }
         }
         if (shippedSkus.size > 0) {
-          const remaining = prev.lines.filter((l) => {
+          const remaining = (prev.lines || []).filter((l) => {
             const raw = l.sku != null ? String(l.sku).trim().toLowerCase() : '';
             return shippedSkus.has(raw);
           });
@@ -885,10 +886,10 @@ class ManifestForm extends PureComponent {
             return null;
           }
           enqueueSnackbar('Nicht ausgelieferte Positionen wurden entfernt.', { variant: 'info' });
-          return { lines: remaining, isDirty: true };
+          nextLines = remaining;
         }
       }
-      return { lines: [], isDirty: true };
+      return { lines: nextLines, isDirty: true };
     });
   }
 
@@ -1181,7 +1182,7 @@ class ManifestForm extends PureComponent {
         {
           kind: cfg.kind,
           partyField: cfg.partyField,
-          requireAtLeastOne: true,
+          requireAtLeastOne: !isEdit,
           externalNumber: cfg.externalNumber,
           isUpdate: isEdit,
           mode,
@@ -1334,7 +1335,7 @@ class ManifestForm extends PureComponent {
             isDirty={this.state.isDirty}
             dirtyFields={this.state.dirtyFields}
             dirtySummary={this.state.dirtySummary}
-            onRestore={this.props.mode === 'edit' && this.state.isDirty ? this.handleRestore : undefined}
+            onRestore={this.props.mode === 'edit' ? this.handleRestore : undefined}
             onPdfUpload={kind === 'delivery' ? this.handlePdfUpload : undefined}
             onPdfDelete={this.handleAttachmentDelete}
             onPdfCreate={kind === 'quote' || kind === 'order' ? this.handleCreatePdf : undefined}
diff --git a/src/components/manifest/ManifestHeader.jsx b/src/components/manifest/ManifestHeader.jsx
index b486a7d..6347547 100644
--- a/src/components/manifest/ManifestHeader.jsx
+++ b/src/components/manifest/ManifestHeader.jsx
@@ -481,27 +481,45 @@ class ManifestHeader extends PureComponent {
             >
               {saving ? 'Speichern…' : 'Speichern'}
             </Button>
-            {isDirty && onRestore && (
-              <Button
-                variant="outlined"
-                color="warning"
-                size="small"
-                startIcon={<RestoreIcon />}
-                disabled={saving || orderCreating}
-                onClick={onRestore}
-                sx={{
-                  height: 34,
-                  fontWeight: 700,
-                  fontSize: '0.8rem',
-                  whiteSpace: 'nowrap',
-                  textTransform: 'none',
-                  borderWidth: 1.5,
-                  '&:hover': { borderWidth: 1.5 },
-                }}
-              >
-                Wiederherstellen
-              </Button>
-            )}
+            {(() => {
+              const canRestore = Boolean(onRestore && isDirty && !saving && !orderCreating);
+              return (
+                <Button
+                  variant="outlined"
+                  color={canRestore ? 'warning' : 'inherit'}
+                  size="small"
+                  startIcon={<RestoreIcon />}
+                  disabled={!canRestore}
+                  onClick={canRestore ? onRestore : undefined}
+                  title={
+                    canRestore
+                      ? 'Änderungen verwerfen und ursprünglichen Stand wiederherstellen'
+                      : 'Keine Änderungen zum Wiederherstellen'
+                  }
+                  sx={{
+                    height: 34,
+                    width: '100%',
+                    fontWeight: 700,
+                    fontSize: '0.8rem',
+                    whiteSpace: 'nowrap',
+                    textTransform: 'none',
+                    borderWidth: 1.5,
+                    '&:hover': { borderWidth: 1.5 },
+                    ...(!canRestore && {
+                      borderColor: 'action.disabled',
+                      color: 'text.disabled',
+                      '&.Mui-disabled': {
+                        borderColor: 'action.disabled',
+                        color: 'text.disabled',
+                        borderWidth: 1.5,
+                      },
+                    }),
+                  }}
+                >
+                  Wiederherstellen
+                </Button>
+              );
+            })()}
             {docId != null && kind === 'delivery' && onOpenBookDialog && Boolean(ledgerSummary && (ledgerSummary.totalPositions > 0 || ledgerSummary.lines?.length > 0 || ledgerSummary.hasTrackStock)) && (
               <Button
                 variant={ledgerSummary?.status === 'booked' ? 'outlined' : 'contained'}
@@ -561,27 +579,56 @@ class ManifestHeader extends PureComponent {
                 {orderCreating ? 'Wird erstellt…' : 'Bestellung erstellen'}
               </Button>
             )}
-            {(kind === 'quote' || kind === 'order' || kind === 'delivery') && onPdfCreate && docId != null && Boolean(number) && (
-              <Button
-                type="button"
-                variant="outlined"
-                startIcon={pdfCreating ? <CircularProgress size={16} color="inherit" /> : <PictureAsPdfIcon />}
-                disabled={saving || pdfCreating || orderCreating}
-                onClick={onPdfCreate}
-                title="PDF erstellen"
-                sx={{
-                  whiteSpace: 'nowrap',
-                  height: 40,
-                  width: '100%',
-                  px: 1.5,
-                  boxSizing: 'border-box',
-                  fontWeight: 600,
-                  fontSize: '0.875rem',
-                }}
-              >
-                {pdfCreating ? 'Wird erstellt…' : 'PDF erstellen'}
-              </Button>
-            )}
+            {(kind === 'quote' || kind === 'order' || kind === 'delivery') && (() => {
+              const canCreatePdf = Boolean(
+                onPdfCreate &&
+                docId != null &&
+                Boolean(number) &&
+                !saving &&
+                !pdfCreating &&
+                !orderCreating
+              );
+              return (
+                <Button
+                  type="button"
+                  variant="outlined"
+                  color={canCreatePdf ? 'primary' : 'inherit'}
+                  startIcon={pdfCreating ? <CircularProgress size={16} color="inherit" /> : <PictureAsPdfIcon />}
+                  disabled={!canCreatePdf}
+                  onClick={canCreatePdf ? onPdfCreate : undefined}
+                  title={
+                    pdfCreating
+                      ? 'PDF wird erstellt…'
+                      : canCreatePdf
+                      ? 'PDF erstellen'
+                      : docId == null
+                      ? 'PDF kann erst nach dem Speichern erstellt werden'
+                      : !number
+                      ? 'Dokumentnummer erforderlich für PDF'
+                      : 'PDF erstellen'
+                  }
+                  sx={{
+                    whiteSpace: 'nowrap',
+                    height: 40,
+                    width: '100%',
+                    px: 1.5,
+                    boxSizing: 'border-box',
+                    fontWeight: 600,
+                    fontSize: '0.875rem',
+                    ...(!canCreatePdf && {
+                      borderColor: 'action.disabled',
+                      color: 'text.disabled',
+                      '&.Mui-disabled': {
+                        borderColor: 'action.disabled',
+                        color: 'text.disabled',
+                      },
+                    }),
+                  }}
+                >
+                  {pdfCreating ? 'Wird erstellt…' : 'PDF erstellen'}
+                </Button>
+              );
+            })()}
             {onPdfUpload ? (
               <FileDropzone
                 accept="application/pdf,.pdf,text/plain,.txt,text/csv,.csv"
diff --git a/src/components/manifest/ManifestLines.jsx b/src/components/manifest/ManifestLines.jsx
index a53d664..1fcdcc9 100644
--- a/src/components/manifest/ManifestLines.jsx
+++ b/src/components/manifest/ManifestLines.jsx
@@ -199,22 +199,42 @@ class ManifestLines extends PureComponent {
               );
             })()}
             {(() => {
-              const hasShippedLines = kind === 'order' && Array.isArray(shipments) && shipments.some((sh) => (sh.lines?.length || 0) > 0);
-              const hasLedgeredLines = kind === 'delivery' && Array.isArray(lines) && lines.some((line) => {
-                const ledgerLine = line?.id != null ? ledgerLinesById?.[line.id] : null;
-                return Boolean(
-                  ledgerLine?.isBooked ||
-                  (ledgerLine && ledgerLine.targetAmount > 0 && ledgerLine.remainingAmount <= 0) ||
-                  (ledgerLine && ledgerLine.bookedAmount > 0) ||
-                  line?.isBooked ||
-                  line?.is_booked
-                );
-              });
-              const disabled = saving || !lines || lines.length === 0 || hasShippedLines || hasLedgeredLines;
-              const title = hasLedgeredLines
-                ? 'Lieferung enthält bereits im Ledger verbuchte Positionen'
-                : hasShippedLines
-                  ? 'Auftrag enthält bereits ausgelieferte Positionen'
+              const shippedSkus = new Set();
+              if (kind === 'order' && Array.isArray(shipments)) {
+                for (const sh of shipments) {
+                  for (const sl of sh.lines || []) {
+                    if (sl.sku) shippedSkus.add(String(sl.sku).trim().toLowerCase());
+                  }
+                }
+              }
+              const allLinesShipped =
+                kind === 'order' &&
+                shippedSkus.size > 0 &&
+                Array.isArray(lines) &&
+                lines.length > 0 &&
+                lines.every((l) => {
+                  const raw = l?.sku != null ? String(l.sku).trim().toLowerCase() : '';
+                  return raw && shippedSkus.has(raw);
+                });
+              const allLinesLedgered =
+                kind === 'delivery' &&
+                Array.isArray(lines) &&
+                lines.length > 0 &&
+                lines.every((line) => {
+                  const ledgerLine = line?.id != null ? ledgerLinesById?.[line.id] : null;
+                  return Boolean(
+                    ledgerLine?.isBooked ||
+                    (ledgerLine && ledgerLine.targetAmount > 0 && ledgerLine.remainingAmount <= 0) ||
+                    (ledgerLine && ledgerLine.bookedAmount > 0) ||
+                    line?.isBooked ||
+                    line?.is_booked
+                  );
+                });
+              const disabled = saving || !lines || lines.length === 0 || allLinesShipped || allLinesLedgered;
+              const title = allLinesLedgered
+                ? 'Alle Positionen der Lieferung sind bereits im Ledger verbucht'
+                : allLinesShipped
+                  ? 'Alle Positionen des Auftrags sind bereits ausgeliefert'
                   : 'Alle Zeilen entfernen';
               return (
                 <Button
diff --git a/src/routes/lieferung/neu.jsx b/src/routes/lieferung/neu.jsx
index 94cb989..cac3024 100644
--- a/src/routes/lieferung/neu.jsx
+++ b/src/routes/lieferung/neu.jsx
@@ -160,6 +160,7 @@ class LieferungNeuPage extends PureComponent {
     this.handleRemoveLine = this.handleRemoveLine.bind(this);
     this.handleMoveLine = this.handleMoveLine.bind(this);
     this.handleRemoveAllLines = this.handleRemoveAllLines.bind(this);
+    this.handleRestore = this.handleRestore.bind(this);
     this.handleSave = this.handleSave.bind(this);
     this.handlePdfUpload = this.handlePdfUpload.bind(this);
     this.handlePdfRescan = this.handlePdfRescan.bind(this);
@@ -686,6 +687,24 @@ class LieferungNeuPage extends PureComponent {
 
   handleRemoveAllLines() {
     this.automat.actions.clearLineitems();
+    this.setState({ lines: [] });
+  }
+
+  handleRestore() {
+    if (!this._initialDoc) return;
+    const base = this._initialDoc;
+    this.automat.actions.setDate(base.date);
+    if (base.partyId != null) {
+      this.automat.actions.setDeliveryEntity(base.partyId);
+    }
+    this.automat.actions.setExternalNumber(base.externalNumber || '');
+    const restoredLines = (base.lines || []).map((l) => ({ ...l }));
+    this.automat.actions.setLineitems(restoredLines);
+    this.automat.actions.setAttachments([...(base.attachments || [])]);
+    this.setState({
+      lines: restoredLines,
+    });
+    enqueueSnackbar('Änderungen verworfen und ursprünglicher Stand wiederhergestellt.', { variant: 'info' });
   }
 
   async handlePdfUpload(file) {
@@ -1331,6 +1350,7 @@ class LieferungNeuPage extends PureComponent {
             onNumberChange={this.handleNumberChange}
             onExternalNumberChange={this.handleExternalNumberChange}
             docId={this.props.docId}
+            onRestore={isEdit ? this.handleRestore : undefined}
             ledgerSummary={this.state.ledgerSummary}
             onOpenBookDialog={this.handleOpenBookDialog}
           />