On May 12, 12:40*pm, "Cimjet" wrote:
If I post a link to the file in question would someone
have a look at it and see if they can make it work.

Yes. That is a "good practice". If you do not have a public file-
sharing website to use, see the list at the bottom. Be sure the file
is "shared" or "sharable". It would be best if you tested the URL
("link") by logging out of the website and simply entering the URL
into a browser to be sure that we will be able to download the file.

For my benefit, it would be best if you uploaded an XL2003-compatible
file. But if that is too much trouble, upload a normal file. If I
cannot open it, someone else probably can.

However, you still need to answer a critical question: when is it
necessary to recompute I50:I53? Only when a cell changes in the
ranges $B$6:$AF$17, $B$21:$AF$32 and $B$36:$AF$47?

Cimjet wrote elsewhe
If I remove the formula for the Range ("I50") and
leave Range ("I51") working, it works perfectly
but with both Range it seem to go in a loop

I believe I answered that, although I would expect that you would get
an infinite loop with either Range assignment.

If you use a SheetChange event macro, you need to disable events in
the macro so that the assignment to a range within the macro does not
trigger another event.

Cimjet wrote elsewhe
I'm not sure what is a Volatile UDF.
I know what is a UDF

A volatile UDF (user-defined function) is a VBA function that is
executed each time any cell in the workbook is modified by some user
operation (editing, sorting, deleting, etc). It is VBA function that
starts with Application.Volatile.

Cimjet wrote:
I can't use that because the problem is that they
keep removing the formula in the cells and they
don't want lock cells (No Protection ) Too many
people protecting worksheets then moving away and
no longer can work with the file.

That's an operational problem you and your management should try to
fix. When an employee, contractor or volunteer leaves, part of the
exit procedure should be to sit down with them and be sure that all
critical files are usable without them.

Usually, it is not difficult to "break" Excel's cell protection
mechanism. Some procedures are described on websites. Search for
"excel cell protection removal" without quotes.

Some free file-sharing websites that people have suggested or used....

Windows Live Skydrive: http://skydrive.live.com
MediaFi http://www.mediafire.com
FileFactory: http://www.filefactory.com
FileSavr: http://www.filesavr.com
FileDropper: http://www.filedropper.com
RapidSha http://www.rapidshare.com
Box.Net: http://www.box.net/files

I use bot.net myself.