diff --git a/Marlin/src/lcd/extui/knutwurst/anycubic_touchscreen.cpp b/Marlin/src/lcd/extui/knutwurst/anycubic_touchscreen.cpp
index df8fef65..13dbec7f 100755
--- a/Marlin/src/lcd/extui/knutwurst/anycubic_touchscreen.cpp
+++ b/Marlin/src/lcd/extui/knutwurst/anycubic_touchscreen.cpp
@@ -990,10 +990,11 @@ void AnycubicTouchscreenClass::RenderCurrentFolder(uint16_t selectedNumber) {
       // Bugfix for non-printable special characters
       // which are now replaced by underscores.
       for (unsigned char i = 0; i <= fileNameLen; i++) {
+        if (isPrintable(fileName[i])) {
           outputString[i] = fileName[i];
-          if (!isPrintable(outputString[i])) {
-            outputString[i] = '_';
-          }
+        } else {
+          outputString[i] = '_';
+        }
       }
 
       // I know, it's ugly, but it's faster than a string lib