I asked the same question a week ago this was the response:
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Here's another idea... far-fetched? Maybe, but I'll throw it on the
table anyway.
Suppose you have a form (switchboard or other) that stays open at all
times; you can have a timer event on it to check the value of a field in
a single record table every two minutes (or whatever). If the value is
not zero, it opens a pop-up form which displays the appropriate message,
stored in another table with two fields, MsgID and MessageText, and
selected based on the value of the field in the former table; a couple
od lines of VBA code are enough to pick up the selected message and put
it in a label's caption (and possibly the form caption as well).
So, whenever you want to do it, all you have to do is change the value
of the field in the single record table.
Taking it a step further, you could also use the same method to kick
users out.
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it just works fine for me i can send users a message that they must close
the programm, and a few minutes later i give a command to close all the
forms/access applications.
good luck!
Harm