diff --git a/dlls/setupapi/misc.c b/dlls/setupapi/misc.c
index a9efa2add47..08c0c794fa7 100644
--- a/dlls/setupapi/misc.c
+++ b/dlls/setupapi/misc.c
@@ -30,6 +30,7 @@
 #include "lzexpand.h"
 #include "softpub.h"
 #include "mscat.h"
+#include "shlobj.h"
 
 #include "wine/unicode.h"
 #include "wine/debug.h"
@@ -197,67 +198,8 @@ LONG WINAPI QueryRegistryValue(HKEY hKey,
  */
 BOOL WINAPI IsUserAdmin(VOID)
 {
-    SID_IDENTIFIER_AUTHORITY Authority = {SECURITY_NT_AUTHORITY};
-    HANDLE hToken;
-    DWORD dwSize;
-    PTOKEN_GROUPS lpGroups;
-    PSID lpSid;
-    DWORD i;
-    BOOL bResult = FALSE;
-
     TRACE("\n");
-
-    if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &hToken))
-    {
-        return FALSE;
-    }
-
-    if (!GetTokenInformation(hToken, TokenGroups, NULL, 0, &dwSize))
-    {
-        if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
-        {
-            CloseHandle(hToken);
-            return FALSE;
-        }
-    }
-
-    lpGroups = MyMalloc(dwSize);
-    if (lpGroups == NULL)
-    {
-        CloseHandle(hToken);
-        return FALSE;
-    }
-
-    if (!GetTokenInformation(hToken, TokenGroups, lpGroups, dwSize, &dwSize))
-    {
-        MyFree(lpGroups);
-        CloseHandle(hToken);
-        return FALSE;
-    }
-
-    CloseHandle(hToken);
-
-    if (!AllocateAndInitializeSid(&Authority, 2, SECURITY_BUILTIN_DOMAIN_RID,
-                                  DOMAIN_ALIAS_RID_ADMINS, 0, 0, 0, 0, 0, 0,
-                                  &lpSid))
-    {
-        MyFree(lpGroups);
-        return FALSE;
-    }
-
-    for (i = 0; i < lpGroups->GroupCount; i++)
-    {
-        if (EqualSid(lpSid, lpGroups->Groups[i].Sid))
-        {
-            bResult = TRUE;
-            break;
-        }
-    }
-
-    FreeSid(lpSid);
-    MyFree(lpGroups);
-
-    return bResult;
+    return IsUserAnAdmin();
 }
 
 
diff --git a/dlls/shell32/shell32.spec b/dlls/shell32/shell32.spec
index 9d4808fc493..b50890b1a0e 100644
--- a/dlls/shell32/shell32.spec
+++ b/dlls/shell32/shell32.spec
@@ -251,7 +251,7 @@
  654 stdcall @(long long) shell32_654 # ReadCabinetState@8
 
  660 stdcall -noname FileIconInit(long)
- 680 stdcall -noname IsUserAdmin()
+ 680 stdcall -noname IsUserAnAdmin()
 
  704 stdcall -noname GUIDFromStringW(wstr ptr)
 
diff --git a/dlls/shell32/shellord.c b/dlls/shell32/shellord.c
index 5eb45074019..2fef9408570 100644
--- a/dlls/shell32/shellord.c
+++ b/dlls/shell32/shellord.c
@@ -1279,13 +1279,79 @@ BOOL WINAPI FileIconInit(BOOL bFullInit)
 {	FIXME("(%s)\n", bFullInit ? "true" : "false");
 	return 0;
 }
+
 /*************************************************************************
- * IsUserAdmin					[SHELL32.680] NT 4.0
+ * IsUserAnAdmin    [SHELL32.680] NT 4.0
  *
+ * Checks whether the current user is a member of the Administrators group.
+ *
+ * PARAMS
+ *     None
+ *
+ * RETURNS
+ *     Success: TRUE
+ *     Failure: FALSE
  */
-HRESULT WINAPI IsUserAdmin(void)
-{	FIXME("stub\n");
-	return TRUE;
+BOOL WINAPI IsUserAnAdmin(VOID)
+{
+    SID_IDENTIFIER_AUTHORITY Authority = {SECURITY_NT_AUTHORITY};
+    HANDLE hToken;
+    DWORD dwSize;
+    PTOKEN_GROUPS lpGroups;
+    PSID lpSid;
+    DWORD i;
+    BOOL bResult = FALSE;
+
+    TRACE("\n");
+    if (!OpenProcessToken(GetCurrentProcess(), TOKEN_QUERY, &hToken))
+    {
+        return FALSE;
+    }
+
+    if (!GetTokenInformation(hToken, TokenGroups, NULL, 0, &dwSize))
+    {
+        if (GetLastError() != ERROR_INSUFFICIENT_BUFFER)
+        {
+            CloseHandle(hToken);
+            return FALSE;
+        }
+    }
+
+    lpGroups = HeapAlloc(GetProcessHeap(), 0, dwSize);
+    if (lpGroups == NULL)
+    {
+        CloseHandle(hToken);
+        return FALSE;
+    }
+
+    if (!GetTokenInformation(hToken, TokenGroups, lpGroups, dwSize, &dwSize))
+    {
+        HeapFree(GetProcessHeap(), 0, lpGroups);
+        CloseHandle(hToken);
+        return FALSE;
+    }
+
+    CloseHandle(hToken);
+    if (!AllocateAndInitializeSid(&Authority, 2, SECURITY_BUILTIN_DOMAIN_RID,
+                                  DOMAIN_ALIAS_RID_ADMINS, 0, 0, 0, 0, 0, 0,
+                                  &lpSid))
+    {
+        HeapFree(GetProcessHeap(), 0, lpGroups);
+        return FALSE;
+    }
+
+    for (i = 0; i < lpGroups->GroupCount; i++)
+    {
+        if (EqualSid(lpSid, lpGroups->Groups[i].Sid))
+        {
+            bResult = TRUE;
+            break;
+        }
+    }
+
+    FreeSid(lpSid);
+    HeapFree(GetProcessHeap(), 0, lpGroups);
+    return bResult;
 }
 
 /*************************************************************************
diff --git a/include/shlobj.h b/include/shlobj.h
index a608a7e359d..01f8368c0b7 100644
--- a/include/shlobj.h
+++ b/include/shlobj.h
@@ -77,6 +77,7 @@ VOID         WINAPI SHUpdateImageW(LPCWSTR,INT,UINT,INT);
 #define             SHUpdateImage WINELIB_NAME_AW(SHUpdateImage)
 int          WINAPI RestartDialog(HWND,LPCWSTR,DWORD);
 int          WINAPI RestartDialogEx(HWND,LPCWSTR,DWORD,DWORD);
+BOOL         WINAPI IsUserAnAdmin(void);
 
 #define SHFMT_ERROR     0xFFFFFFFFL  /* Error on last format, drive may be formattable */
 #define SHFMT_CANCEL    0xFFFFFFFEL  /* Last format was cancelled */