diff --git a/aas-gui/Frontend/aas-web-gui/src/components/MainWindow.vue b/aas-gui/Frontend/aas-web-gui/src/components/MainWindow.vue
index 0c2b93f..c0ce756 100644
--- a/aas-gui/Frontend/aas-web-gui/src/components/MainWindow.vue
+++ b/aas-gui/Frontend/aas-web-gui/src/components/MainWindow.vue
@@ -113,21 +113,23 @@ export default defineComponent({
 				curCol = e.target.parentElement;                        // the current element that will be scaled
 				nxtCol = curCol.nextElementSibling;                     // selects the divider
         if(nxtCol) nxtCol = nxtCol.nextElementSibling;          // the next element that will be scaled too
-				pageX = e.pageX;                                        // the current x position of the mouse
+				pageX = parseInt(e.pageX);                                        // the current x position of the mouse
         curColWidth = parseInt(curCol.offsetWidth);             // the current width of the current element
 				if(nxtCol) nxtColWidth = parseInt(nxtCol.offsetWidth);  // the current width of the next element
 			});
       // Eventlistener to scale the current and next Window when the mouse is moved
 			document.addEventListener('mousemove', function(e: any) {
-        if(!curCol) return;                                                                                       // if no element is selected return
-        let screenWidth = document.getElementsByTagName('html')[0].clientWidth;                                   // the width of the screen (Window) excluding the scrollbar
-        let navigationDrawer: any = document.getElementsByClassName('leftMenu')[0];                               // the width of the navigation drawer
-        let isDrawerOpen: boolean = navigationDrawer.style.transform == 'translateX(0%)';                         // checks if the navigation drawer is open
-        screenWidth = screenWidth - (isDrawerOpen ? 336 : 0);                                                     // if the navigation drawer is open subtract the width of the navigation drawer from the screen width
-        let diffX = parseInt(e.pageX) - pageX;                                                                    // amount the header was dragged (minus - left, plus - right)
-        // TODO: prevent negative width
-        if(curCol) curCol.style.width = (100 - ((screenWidth - curColWidth - diffX) / screenWidth) * 100) + '%';  // scale the current Column (Window)
-        if(nxtCol) nxtCol.style.width = (100 - ((screenWidth - nxtColWidth + diffX) / screenWidth) * 100) + '%';  // scale the next Column (Window) if it exists
+        if(!curCol) return;                                                                  // if no element is selected return
+        let screenWidth = document.documentElement.clientWidth;                              // the width of the screen (Window) excluding the scrollbar
+        let navigationDrawer: any = document.getElementsByClassName('leftMenu')[0];          // the width of the navigation drawer
+        let isDrawerOpen: boolean = navigationDrawer.style.transform == 'translateX(0px)';  // checks if the navigation drawer is open
+        screenWidth = screenWidth - (isDrawerOpen ? navigationDrawer.clientWidth : 0);      // if the navigation drawer is open subtract the width of the navigation drawer from the screen width
+        let diffX = parseInt(e.pageX) - pageX;                                              // amount the header was dragged (minus - left, plus - right)
+        let minimalColWith = 200;
+        if ((curColWidth + diffX) >= minimalColWith && (nxtColWidth - diffX) >= minimalColWith) {
+          if(curCol) curCol.style.width = (100 - ((screenWidth - (curColWidth + diffX)) / screenWidth) * 100) + '%';  // scale the current Column (Window)
+          if(nxtCol) nxtCol.style.width = (100 - ((screenWidth - (nxtColWidth - diffX)) / screenWidth) * 100) + '%';  // scale the next Column (Window) if it exists
+        }
 			});
       // Eventlistener to clear the local Variables mouse up
 			document.addEventListener('mouseup', function() {