diff --git a/dlls/advapi32/registry.c b/dlls/advapi32/registry.c
index 53b645910d1e2878382074acb6f94fca32ad1512..f18e34fe81facad2450648ad6175a42ebc036024 100644
--- a/dlls/advapi32/registry.c
+++ b/dlls/advapi32/registry.c
@@ -3273,7 +3273,7 @@ LSTATUS WINAPI RegLoadMUIStringW(HKEY hKey, LPCWSTR pwszValue, LPWSTR pwszBuffer
 
         /* Format of the expanded value is 'path_to_dll,-resId' */
         if (!pComma || pComma[1] != '-') {
-            result = ERROR_BADKEY;
+            result = ERROR_INVALID_DATA;
             goto cleanup;
         }
 
diff --git a/dlls/advapi32/tests/registry.c b/dlls/advapi32/tests/registry.c
index 855f5a8dcc8d1dabcc91f5ddc9dc55f804547f74..0f4e196d0d2ebd924d78d1151c8d978909f05b8c 100644
--- a/dlls/advapi32/tests/registry.c
+++ b/dlls/advapi32/tests/registry.c
@@ -3859,7 +3859,7 @@ static void test_RegLoadMUIString(void)
         /* 0 */
         { "",                  REG_SZ,        FALSE, ERROR_INVALID_DATA },
         { "not a MUI string",  REG_SZ,        FALSE, ERROR_INVALID_DATA },
-        { "@unknown.dll",      REG_SZ,        TRUE,  ERROR_INVALID_DATA, 0, TRUE },
+        { "@unknown.dll",      REG_SZ,        TRUE,  ERROR_INVALID_DATA },
         { "@unknown.dll,-10",  REG_SZ,        TRUE,  ERROR_FILE_NOT_FOUND },
         /*  4 */
         { with_env_var,        REG_SZ,        FALSE, ERROR_SUCCESS },
@@ -3867,7 +3867,7 @@ static void test_RegLoadMUIString(void)
         { "%WineMuiTest1%",    REG_EXPAND_SZ, TRUE,  ERROR_INVALID_DATA },
         { "@%WineMuiTest2%",   REG_EXPAND_SZ, TRUE,  ERROR_SUCCESS },
         /*  8 */
-        { "@%WineMuiExe%,a",   REG_SZ,        FALSE, ERROR_INVALID_DATA, 0, TRUE },
+        { "@%WineMuiExe%,a",   REG_SZ,        FALSE, ERROR_INVALID_DATA },
         { "@%WineMuiExe%,-4",  REG_SZ,        FALSE, ERROR_NOT_FOUND, ERROR_FILE_NOT_FOUND, TRUE },
         { "@%WineMuiExe%,-39", REG_SZ,        FALSE, ERROR_RESOURCE_NAME_NOT_FOUND, 0, TRUE },
         { "@%WineMuiDat%,-16", REG_EXPAND_SZ, FALSE, ERROR_BAD_EXE_FORMAT, ERROR_FILE_NOT_FOUND, TRUE },