OK, I resuscitated my old XP machine: doesn't work, even with a manifest. What is most irritating is that SendMessage and GetLastError insist that everything is just fine. But it isn't.
Conclusion: Works fine with Win7 and a manifest that specifies common controls version 6, otherwise not. I suggest to set the text manually, and clear it when the control gets the focus for the first time.
P.S.:
Fascinating ... note this refers to combobox, not edit control:
You need to use EM_SETCUEBANNER As Integer = &H1501 for XP and CB_SETCUEBANNER As UInteger = &H1703 for Windows 7.
Check this also:
The problem in Windows XP isn’t that the cue banner shows up in an East Asian Language; it’s that if an East Asian language pack is installed, then the cue banner doesn’t show up at all
Could be the reason why it doesn't show on my old machine, because it does have an East Asian Language pack.