Why other worksheets changed when I change the value on in the cell on one worksheet?

You may have accidentally grouped the sheets together - when in this state, anything that you do on one sheet will be reflected on all the grouped sheets. To undo the grouping, right click on a sheet tab and select Ungroup sheets (or you can just click on a sheet tab that has not been grouped - the colour of the tab is different). You can group sheets together by holding down the SHIFT key and then clicking on another sheet tab, so you could easily have done this by accident.

If you have not saved the file then you can get back to where you started from by closing the current file and then re-opening it, or you might have to click Undo a few times to get back to where you were.

Hope this helps.

Pete

Thank you very much, Pete! It works!!!!! I'm so happyyyyyyyyy

Thanks again for your help.

Glad to hear it.

If that takes care of your original question, please select Thread Tools from the menu above your first post and mark this thread as SOLVED.

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Pete