>Hello All,
>I have a need to remove all index tags from my tables ( for performance reasons ) then reinstate them, I saw some code years ago that modified the header using low level functions,did something then set the header back as was, anyone have any ideas?

DELETE TAG ALL does exactly what you need but would require that you rebuild the indexes at a later time to reinstate them; if data is being changed while the tags are disabled, you'd need to do this IAC.

If no data is being changed, there's no reason to do this; simply SET ORDER TO 0, or if you need the file in other than natural record order, a SQL Select to a cursor, acting against the cursor, should not involve any record skip overhead.