diff --git a/src/java.desktop/windows/native/libawt/windows/awt_Font.cpp b/src/java.desktop/windows/native/libawt/windows/awt_Font.cpp
index 608583bdf07..fac9a022209 100644
--- a/src/java.desktop/windows/native/libawt/windows/awt_Font.cpp
+++ b/src/java.desktop/windows/native/libawt/windows/awt_Font.cpp
@@ -1790,10 +1790,16 @@ void CCombinedSegTable::GetEUDCFileName(LPWSTR lpszFileName, int cchFileName)
     DWORD dwBytes = sizeof(szFileName);
     // try Typeface-specific EUDC font
     char szTmpName[80];
-    VERIFY(::WideCharToMultiByte(CP_ACP, 0, szFamilyName, -1,
-        szTmpName, sizeof(szTmpName), NULL, NULL));
-    LONG lStatus = ::RegQueryValueExA(hKey, (LPCSTR) szTmpName,
-        NULL, &dwType, szFileName, &dwBytes);
+    int nb = ::WideCharToMultiByte(CP_ACP, 0, szFamilyName, -1,
+        szTmpName, sizeof(szTmpName), NULL, NULL);
+    VERIFY(nb);
+
+    LONG lStatus = 1;
+    if (nb > 0) {
+        lStatus = ::RegQueryValueExA(hKey, (LPCSTR) szTmpName,
+                                     NULL, &dwType, szFileName, &dwBytes);
+    }
+
     BOOL fUseDefault = FALSE;
     if (lStatus != ERROR_SUCCESS){ // try System default EUDC font
         if (m_fTTEUDCFileExist == FALSE)
diff --git a/src/java.desktop/windows/native/libawt/windows/awt_PrintJob.cpp b/src/java.desktop/windows/native/libawt/windows/awt_PrintJob.cpp
index 9836923fca5..5d3f337036d 100644
--- a/src/java.desktop/windows/native/libawt/windows/awt_PrintJob.cpp
+++ b/src/java.desktop/windows/native/libawt/windows/awt_PrintJob.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1996, 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1996, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -3925,9 +3925,13 @@ static void throwPrinterException(JNIEnv *env, DWORD err) {
                   sizeof(t_errStr),
                   NULL );
 
-    WideCharToMultiByte(CP_UTF8, 0, t_errStr, -1,
+    int nb = WideCharToMultiByte(CP_UTF8, 0, t_errStr, -1,
                         errStr, sizeof(errStr), NULL, NULL);
-    JNU_ThrowByName(env, PRINTEREXCEPTION_STR, errStr);
+    if (nb > 0) {
+        JNU_ThrowByName(env, PRINTEREXCEPTION_STR, errStr);
+    } else {
+        JNU_ThrowByName(env, PRINTEREXCEPTION_STR, "secondary error during OS message extraction");
+    }
 }
 
 
diff --git a/src/java.desktop/windows/native/libjsound/PLATFORM_API_WinOS_Charset_Util.cpp b/src/java.desktop/windows/native/libjsound/PLATFORM_API_WinOS_Charset_Util.cpp
index 6179d7bbf4b..0f207437523 100644
--- a/src/java.desktop/windows/native/libjsound/PLATFORM_API_WinOS_Charset_Util.cpp
+++ b/src/java.desktop/windows/native/libjsound/PLATFORM_API_WinOS_Charset_Util.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -35,16 +35,25 @@ LPSTR UnicodeToUTF8(const LPCWSTR lpUnicodeStr)
 {
     DWORD dwUTF8Len = WideCharToMultiByte(CP_UTF8, 0, lpUnicodeStr, -1, nullptr, 0, nullptr, nullptr);
     LPSTR lpUTF8Str = new CHAR[dwUTF8Len];
+    if (lpUTF8Str == NULL) return NULL;
     memset(lpUTF8Str, 0, sizeof(CHAR) * (dwUTF8Len));
-    WideCharToMultiByte(CP_UTF8, 0, lpUnicodeStr, -1, lpUTF8Str, dwUTF8Len, nullptr, nullptr);
-    return lpUTF8Str;
+    int nb = WideCharToMultiByte(CP_UTF8, 0, lpUnicodeStr, -1, lpUTF8Str, dwUTF8Len, nullptr, nullptr);
+    if (nb > 0) {
+        return lpUTF8Str;
+    }
+    delete[] lpUTF8Str;
+    return NULL;
 }
 
 void UnicodeToUTF8AndCopy(LPSTR dest, LPCWSTR src, SIZE_T maxLength) {
     LPSTR utf8EncodedName = UnicodeToUTF8(src);
-    strncpy(dest, utf8EncodedName, maxLength - 1);
-    delete[] utf8EncodedName;
-    dest[maxLength - 1] = '\0';
+    if (utf8EncodedName != NULL) {
+        strncpy(dest, utf8EncodedName, maxLength - 1);
+        delete[] utf8EncodedName;
+        dest[maxLength - 1] = '\0';
+    } else {
+        if (maxLength > 0) dest[0] = '\0';
+    }
 }
 
 #ifdef __cplusplus