diff --git a/reactos/lib/shell32/pidl.c b/reactos/lib/shell32/pidl.c
index fb6f1b0c86b..38269b87277 100644
--- a/reactos/lib/shell32/pidl.c
+++ b/reactos/lib/shell32/pidl.c
@@ -1297,16 +1297,17 @@ HRESULT _SHGetPathFromIDListA(LPCITEMIDLIST pidl, LPSTR pszPath, UINT uOutSize)
 	LPSTR pstr;
 	LPSTR end = pszPath + uOutSize;
 
- 	if (_ILIsMyComputer(pidl)) { /* optimized loop to retrieve file system paths */
+	/* If the item ID list begins at "My Computer", we can use
+	   an optimized loop to retrieve file system paths. */
+ 	if (_ILIsMyComputer(pidl)) {
 	    LPCITEMIDLIST p = ILGetNext(pidl);
 	    LPSTR txt;
 
 	    pstr = pszPath;
-	    end = pszPath + MAX_PATH;
 
 	    while(p && p->mkid.cb && pstr<end) {
 		if (_ILIsSpecialFolder(p))
-		    break;
+		    return E_INVALIDARG;
 
 		txt = _ILGetTextPointer(p);
 		if (!txt)
@@ -1329,33 +1330,26 @@ HRESULT _SHGetPathFromIDListA(LPCITEMIDLIST pidl, LPSTR pszPath, UINT uOutSize)
 
 	pstr = pszPath;
 
-	hr = SHGetDesktopFolder(&desktop);
+	/* The only other valid case is a simple PIDL rooted at desktop level */
+        if (_ILIsValue(pidl) && _ILIsPidlSimple(pidl)) {
+	    hr = SHGetDesktopFolder(&desktop);
 
-	if (SUCCEEDED(hr)) {
-            if (_ILIsValue(pidl)) {
+	    if (SUCCEEDED(hr)) {
 		hr = SHGetSpecialFolderPathA(0, pszPath, CSIDL_DESKTOP, FALSE);
 
 		if (SUCCEEDED(hr)) {
 		    pstr = PathAddBackslashA(pszPath);
 		    hr = IShellFolder_GetDisplayNameOf(desktop, pidl, SHGDN_FORPARSING, &str);
 		}
+
+		IShellFolder_Release(desktop);
 	    }
-	    else
-	        hr = IShellFolder_GetDisplayNameOf(desktop, pidl, SHGDN_FORPARSING, &str);
+	} else
+	    return E_INVALIDARG;
 
-	    IShellFolder_Release(desktop);
-	}
-
-	if (SUCCEEDED(hr)) {
+	if (SUCCEEDED(hr))
 	    hr = StrRetToStrNA(pstr, end-pstr, &str, pidl);
 
-	    /* don't allow to return displaynames of the form "::{guid}" */
-	    if (pstr[0]==':' && pstr[1]==':') {
-	        *pszPath = '\0';
-	        hr = E_FAIL;
-	    }
-	}
-
 	TRACE_(shell)("-- %s, 0x%08lx\n",pszPath, hr);
 	return hr;
 }
@@ -1401,7 +1395,9 @@ HRESULT _SHGetPathFromIDListW(LPCITEMIDLIST pidl, LPWSTR pszPath, UINT uOutSize)
 	LPWSTR pstr;
 	LPWSTR end = pszPath + uOutSize;
 
- 	if (_ILIsMyComputer(pidl)) { /* optimized loop to retrieve file system paths */
+	/* If the item ID list begins at "My Computer", we can use
+	   an optimized loop to retrieve file system paths. */
+ 	if (_ILIsMyComputer(pidl)) {
 	    LPCITEMIDLIST p = ILGetNext(pidl);
 	    LPSTR txt;
 
@@ -1409,7 +1405,7 @@ HRESULT _SHGetPathFromIDListW(LPCITEMIDLIST pidl, LPWSTR pszPath, UINT uOutSize)
 
 	    while(p && p->mkid.cb && pstr<end) {
 		if (_ILIsSpecialFolder(p))
-		    break;
+		    return E_INVALIDARG;
 
 		txt = _ILGetTextPointer(p);
 		if (!txt)
@@ -1433,33 +1429,26 @@ HRESULT _SHGetPathFromIDListW(LPCITEMIDLIST pidl, LPWSTR pszPath, UINT uOutSize)
 
 	pstr = pszPath;
 
-	hr = SHGetDesktopFolder(&desktop);
+	/* The only other valid case is a simple PIDL rooted at desktop level */
+        if (_ILIsValue(pidl) && _ILIsPidlSimple(pidl)) {
+	    hr = SHGetDesktopFolder(&desktop);
 
-	if (SUCCEEDED(hr)) {
-            if (_ILIsValue(pidl)) {
+	    if (SUCCEEDED(hr)) {
 		hr = SHGetSpecialFolderPathW(0, pszPath, CSIDL_DESKTOP, FALSE);
 
 		if (SUCCEEDED(hr)) {
 		    pstr = PathAddBackslashW(pszPath);
 		    hr = IShellFolder_GetDisplayNameOf(desktop, pidl, SHGDN_FORPARSING, &str);
 		}
+
+		IShellFolder_Release(desktop);
 	    }
-	    else
-	        hr = IShellFolder_GetDisplayNameOf(desktop, pidl, SHGDN_FORPARSING, &str);
+	} else
+	    return E_INVALIDARG;
 
-	    IShellFolder_Release(desktop);
-	}
-
-	if (SUCCEEDED(hr)) {
+	if (SUCCEEDED(hr))
 	    hr = StrRetToStrNW(pstr, end-pstr, &str, pidl);
 
-	    /* don't allow to return displaynames of the form "::{guid}" */
-	    if (pstr[0]==':' && pstr[1]==':') {
-	        *pszPath = '\0';
-	        hr = E_FAIL;
-	    }
-	}
-
 	TRACE_(shell)("-- %s, 0x%08lx\n",debugstr_w(pszPath), hr);
 	return hr;
 }
diff --git a/reactos/lib/shell32/shlcpanel.c b/reactos/lib/shell32/shlcpanel.c
index a4458bafa41..4fb193e0787 100644
--- a/reactos/lib/shell32/shlcpanel.c
+++ b/reactos/lib/shell32/shlcpanel.c
@@ -76,13 +76,13 @@ static ICOM_VTABLE(IShellExecuteHookW) vt_ShellExecuteHookW;
 static ICOM_VTABLE(IShellExecuteHookA) vt_ShellExecuteHookA;
 
 #define _IPersistFolder2_Offset	    ((int)(&(((ICPanelImpl*)0)->lpVtblPersistFolder2)))
-#define _ICOM_THIS_From_IPersistFolder2(class, name) class* This =(class*)(((char*)name)-_IPersistFolder2_Offset);
+#define _ICOM_THIS_From_IPersistFolder2(class, name) class* This = (class*)(((char*)name)-_IPersistFolder2_Offset);
 
 #define IShellExecuteHookW_Offset   ((int)(&(((ICPanelImpl*)0)->lpVtblShellExecuteHookW)))
-#define _ICOM_THIS_From_IShellExecuteHookW(class, name) class* This =(class*)(((char*)name)-IShellExecuteHookW_Offset);
+#define _ICOM_THIS_From_IShellExecuteHookW(class, name) class* This = (class*)(((char*)name)-IShellExecuteHookW_Offset);
 
 #define IShellExecuteHookA_Offset   ((int)(&(((ICPanelImpl*)0)->lpVtblShellExecuteHookA)))
-#define _ICOM_THIS_From_IShellExecuteHookA(class, name) class* This =(class*)(((char*)name)-IShellExecuteHookA_Offset);
+#define _ICOM_THIS_From_IShellExecuteHookA(class, name) class* This = (class*)(((char*)name)-IShellExecuteHookA_Offset);
 
 
 /*
@@ -381,19 +381,19 @@ ISF_ControlPanel_fnGetUIObjectOf(IShellFolder2 * iface,
 	*ppvOut = NULL;
 
 	if (IsEqualIID(riid, &IID_IContextMenu) &&(cidl >= 1)) {
-	    pObj =(LPUNKNOWN) ISvItemCm_Constructor((IShellFolder *) iface, This->pidlRoot, apidl, cidl);
+	    pObj = (LPUNKNOWN) ISvItemCm_Constructor((IShellFolder *) iface, This->pidlRoot, apidl, cidl);
 	    hr = S_OK;
 	} else if (IsEqualIID(riid, &IID_IDataObject) &&(cidl >= 1)) {
-	    pObj =(LPUNKNOWN) IDataObject_Constructor(hwndOwner, This->pidlRoot, apidl, cidl);
+	    pObj = (LPUNKNOWN) IDataObject_Constructor(hwndOwner, This->pidlRoot, apidl, cidl);
 	    hr = S_OK;
 	} else if (IsEqualIID(riid, &IID_IExtractIconA) &&(cidl == 1)) {
 	    pidl = ILCombine(This->pidlRoot, apidl[0]);
-	    pObj =(LPUNKNOWN) IExtractIconA_Constructor(pidl);
+	    pObj = (LPUNKNOWN) IExtractIconA_Constructor(pidl);
 	    SHFree(pidl);
 	    hr = S_OK;
 	} else if (IsEqualIID(riid, &IID_IExtractIconW) &&(cidl == 1)) {
 	    pidl = ILCombine(This->pidlRoot, apidl[0]);
-	    pObj =(LPUNKNOWN) IExtractIconW_Constructor(pidl);
+	    pObj = (LPUNKNOWN) IExtractIconW_Constructor(pidl);
 	    SHFree(pidl);
 	    hr = S_OK;
 	} else if ((IsEqualIID(riid,&IID_IShellLinkW) || IsEqualIID(riid,&IID_IShellLinkA))