Index: dll/win32/setupapi/queue.c
===================================================================
--- dll/win32/setupapi/queue.c	(revision 73394)
+++ dll/win32/setupapi/queue.c	(working copy)
@@ -996,14 +996,31 @@
 
     hSource = LZOpenFileW((LPWSTR)source, &OfStruct, OF_READ);
     if (hSource < 0)
+    {
+        ERR("LZOpenFileW(1) error %d %s\n", (int)hSource, debugstr_w(source));
         return FALSE;
+    }
 
     /* Get a temp file name */
-    GetTempPathW(sizeof(TempPath) / sizeof(WCHAR), TempPath);
-    GetTempFileNameW(TempPath, L"", 0, TempFile);
+    if (!GetTempPathW(sizeof(TempPath) / sizeof(WCHAR), TempPath))
+    {
+        ERR("GetTempPathW error\n");
+        return FALSE;
+    }
+    if (!GetTempFileNameW(TempPath, L"", 0, TempFile))
+    {
+        ERR("GetTempFileNameW(%s) error\n", debugstr_w(TempPath));
+        return FALSE;
+    }
 
     /* Extract the compressed file to a temp location */
     hTemp = LZOpenFileW(TempFile, &OfStruct, OF_CREATE);
+    if (hTemp < 0)
+    {
+        ERR("LZOpenFileW(2) error %d %s\n", (int)hTemp, debugstr_w(TempFile));
+        return FALSE;
+    }
+
     LZCopy(hSource, hTemp);
     LZClose(hSource);
     LZClose(hTemp);
