See if this will do it.
In Registry Editor, locate the following registry subkey: HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\C ommon
1. Click the registry subkey, point to New on the Edit menu, and then click Key.
2. Type Security, and then press ENTER to name the key.
3. On the Edit menu, point to New, and then click DWORD Value.
4. Type DisableHyperlinkWarning, and then press ENTER to name the entry.
5. In the right pane, right-click DisableHyperlinkWarning, and then click Modify.
6. In the Edit DWORD Value dialog box, click Decimal, and then type 1 under Value data.
Note A value of 0 enables the hyperlink warning message. A value of 1 disables the hyperlink warning message.
7. Click OK.
8. Exit Registry Editor.