diff --git a/include/wx/msw/textctrl.h b/include/wx/msw/textctrl.h
index 14265e7983..1a81e44d71 100644
--- a/include/wx/msw/textctrl.h
+++ b/include/wx/msw/textctrl.h
@@ -203,11 +203,11 @@ protected:
     // the limit is due to a previous call to SetMaxLength() and not built in)
     bool HasSpaceLimit(unsigned int *len) const;
 
-    // call this to increase the size limit (will do nothing if the current
-    // limit is big enough)
+    // Used by EN_MAXTEXT handler to increase the size limit (will do nothing
+    // if the current limit is big enough). Should never be called directly.
     //
-    // returns true if we increased the limit to allow entering more text,
-    // false if we hit the limit set by SetMaxLength() and so didn't change it
+    // Returns true if we increased the limit to allow entering more text,
+    // false if we hit the limit set by SetMaxLength() and so didn't change it.
     bool AdjustSpaceLimit();
 
 #if wxUSE_RICHEDIT && (!wxUSE_UNICODE || wxUSE_UNICODE_MSLU)
diff --git a/src/msw/textctrl.cpp b/src/msw/textctrl.cpp
index dfdf2c6e3f..473aa0c36e 100644
--- a/src/msw/textctrl.cpp
+++ b/src/msw/textctrl.cpp
@@ -2149,13 +2149,23 @@ bool wxTextCtrl::AdjustSpaceLimit()
     unsigned int len = ::GetWindowTextLength(GetHwnd());
     if ( len >= limit )
     {
+        unsigned long increaseBy;
+
         // We need to increase the size of the buffer and to avoid increasing
         // it too many times make sure that we make it at least big enough to
-        // fit all the text we are currently inserting into the control.
-        unsigned long increaseBy = gs_lenOfInsertedText.top();
+        // fit all the text we are currently inserting into the control, if
+        // we're inserting any, i.e. if we're called from DoWriteText().
+        if ( !gs_lenOfInsertedText.empty() )
+        {
+            increaseBy = gs_lenOfInsertedText.top();
 
-        // Indicate to the caller that we increased the limit.
-        gs_lenOfInsertedText.top() = -1;
+            // Indicate to the caller that we increased the limit.
+            gs_lenOfInsertedText.top() = -1;
+        }
+        else // Not inserting text, must be text actually typed by user.
+        {
+            increaseBy = 0;
+        }
 
         // But also increase it by at least 32KB chunks -- again, to avoid
         // doing it too often -- and round it up to 32KB in any case.