List possible filenames in Open File dialog box

Hi All,
Since new in Windows 7, whenever I have an Open File dialog box and I start typing into the filename field, it displays all possible filenames that match what I've typed so far.
Now this function is gone, I must have unknowingly changed some setting (or maybe updates did). How do I get it back?

Note: I'm not talking about "recent files" with the arrow button to drop them down; but matching filenames that drop down automatically.
For instance, in an Open File dialog box (any program - not just MS) if say I start typing P files drop down:
PA1
PA2
PA3
PB1
PB2
PB3
etc.
If I continue typing B then only the PB files are left, drop down list is now only
PB1
PB2
PB3

Thanks in anticipation,
Rob

Check out Internet Options / Advanced / Browsing / Use inline AutoComplete in file explorer....

That's fixed it.
Thank-you.