THX for the Reply
The Informations on the link where very helpful
Lots of thoes things I already do like it is explained. Some more, some less because tehere are thing that can´t fit into our needs. Now the specific questions:
The main thing that I´m thinking about is how to update a existing application that is used by more than one user.
Saving it on the local PC's was my first tought and how i can see thats the right way
Now there are two main questions:
1. How to update the FE?
2. How to update tables in the BE?
3. How to "kick" all users out of the application when they "don´t want" or forget to do it on they'r own.
For the first question i have a Idea:
I would like that every user can desit when he eants to make the update, because some have more time some less and that is never at the same time. Because of that i want to make a button what makes the update. Of course (the update procedure is that the old FE file will be overwriten by the new one) I can do that just form the FE application. I managed it like this:
In the FE application is a button on witch klick it opens a other Application (update application) and closes the FE. The update application then just copy a new FE over the old one. I always use the same folder where i store the new FE and the FE is always saved on the "C:\" (no Folder). At this time i´m testing that solution but it migth be te right one

if someone has sugestions or warnings pleas let me know.
The 2 question is more dificult and i don´t thing that there is such an easy way for solwing it like for the first one

future fields are not something for me, because even this constalation od fields is hard to folow (and i made that thing

). Because i don´t think there is a good solution for the 2 question there is the 3 question. By kicking all users form the application I´ll have my time do work on the BE. There fore i could use just a table where i store a value 1 or 0. In the FE i could check that value in defined time intervals and if it is for example 1 it will notice the user that the application will be shut down for maintance. Something similar i will use for the FE updates where i sotre the version of the FE in a BE table and the FE that is in use always checks (at the startup) if it is the newest one. If it is it just displays on the start form that it is uptodate and if not it shows that there is a new one and alwso the version number of the old and the new one.