diff --git a/public/userarea/process_import_xls2.php b/public/userarea/process_import_xls2.php
index 25e4bd2..5a79ba0 100644
--- a/public/userarea/process_import_xls2.php
+++ b/public/userarea/process_import_xls2.php
@@ -74,6 +74,105 @@ function cleanCellText($value): string
     return trim($cleaned ?? $raw);
 }
 
+/**
+ * Pre-clean an .xlsx by streaming out "ghost" cells: empty, self-closing
+ * <c .../> (and <c ...></c>) elements that carry only leftover styling.
+ */
+function slimXlsxGhostCells(string $path): ?string
+{
+    if (!class_exists('ZipArchive')) {
+        return null;
+    }
+
+    $slim = $path . '.slim.xlsx';
+
+    try {
+        if (!copy($path, $slim)) {
+            return null;
+        }
+
+        // Phase 1: stream-strip each worksheet to a temp file (low memory).
+        $zip = new ZipArchive();
+        if ($zip->open($slim) !== true) {
+            @unlink($slim);
+            return null;
+        }
+
+        $temps = [];
+        for ($i = 0; $i < $zip->numFiles; $i++) {
+            $name = $zip->getNameIndex($i);
+            if (!preg_match('#^xl/worksheets/sheet\d+\.xml$#', $name)) {
+                continue;
+            }
+
+            $in = $zip->getStream($name);
+            if (!$in) {
+                continue;
+            }
+
+            $tmp = tempnam(sys_get_temp_dir(), 'slim');
+            $out = fopen($tmp, 'w');
+            $carry = '';
+
+            while (!feof($in)) {
+                $chunk = fread($in, 4194304);
+                if ($chunk === '' || $chunk === false) {
+                    break;
+                }
+                // Only process up to the last complete '>' so a cell tag is
+                // never split across a chunk boundary; carry the remainder.
+                $buf = $carry . $chunk;
+                $lastGt = strrpos($buf, '>');
+                if ($lastGt === false) {
+                    $carry = $buf;
+                    continue;
+                }
+                $proc = substr($buf, 0, $lastGt + 1);
+                $carry = substr($buf, $lastGt + 1);
+                $proc = preg_replace(['#<c [^>]*/>#', '#<c [^>]*></c>#'], '', $proc);
+                fwrite($out, $proc);
+            }
+            if ($carry !== '') {
+                fwrite($out, $carry);
+            }
+            fclose($in);
+            fclose($out);
+            $temps[$name] = $tmp;
+        }
+        $zip->close();
+
+        if (!$temps) {
+            @unlink($slim);
+            return null;
+        }
+
+        // Phase 2: swap the stripped worksheets back into the archive.
+        $zip = new ZipArchive();
+        if ($zip->open($slim) !== true) {
+            foreach ($temps as $t) {
+                @unlink($t);
+            }
+            @unlink($slim);
+            return null;
+        }
+        foreach ($temps as $name => $tmp) {
+            $zip->deleteName($name);
+            $zip->addFile($tmp, $name);
+        }
+        $zip->close(); // addFile streams from disk here, so unlink only after.
+
+        foreach ($temps as $t) {
+            @unlink($t);
+        }
+
+        return $slim;
+    } catch (\Throwable $e) {
+        error_log('slimXlsxGhostCells failed: ' . $e->getMessage());
+        @unlink($slim);
+        return null;
+    }
+}
+
 try {
     // Quando il body POST supera post_max_size, PHP scarta $_POST e $_FILES
     // (warning "Content-Length exceeds the limit ... in Unknown on line 0") e lo
@@ -198,10 +297,28 @@ try {
             if (empty($mappings)) {
                 $response['error'] = "Nessun mapping trovato per il template con ID $template_id";
             } else {
-                // Carica il file rinominato con PHPSpreadsheet
-                $reader = IOFactory::createReaderForFile($destination);
+                // Pre-clean ghost cells for .xlsx so a bloated worksheet (millions
+                // of empty styled cells) doesn't make the load time out. Falls back
+                // to the original file if slimming fails for any reason.
+                $loadPath = $destination;
+                $slimPath = null;
+                if (preg_match('/\.xlsx$/i', $destination)) {
+                    $slimPath = slimXlsxGhostCells($destination);
+                    if ($slimPath !== null) {
+                        $loadPath = $slimPath;
+                        error_log("Ghost-cell pre-clean applied, loading slimmed copy: $slimPath");
+                    }
+                }
+
+                // Carica il file con PHPSpreadsheet.
+                $reader = IOFactory::createReaderForFile($loadPath);
                 $reader->setReadEmptyCells(false);
-                $spreadsheet = $reader->load($destination);
+                $spreadsheet = $reader->load($loadPath);
+
+                // The slimmed copy is only needed for parsing; drop it now.
+                if ($slimPath !== null) {
+                    @unlink($slimPath);
+                }
 
                 $sheetCount = $spreadsheet->getSheetCount();
                 $sheetNames = $spreadsheet->getSheetNames();