diff --git a/src/xpra/platform/win32/clipboard.py b/src/xpra/platform/win32/clipboard.py
index 4e76fbd7ec..769bad7f09 100644
--- a/src/xpra/platform/win32/clipboard.py
+++ b/src/xpra/platform/win32/clipboard.py
@@ -257,7 +257,7 @@ def set_clipboard_text(self, text):
             return
         log("MultiByteToWideChar wlen=%i", wlen)
         #allocate some memory for it:
-        buf = GlobalAlloc(GMEM_MOVEABLE, wlen*2)
+        buf = GlobalAlloc(GMEM_MOVEABLE, (wlen+1)*2)
         if not buf:
             return
         log("GlobalAlloc buf=%#x", buf)