thanks davegri
how about changing the form size unit as "inch" ?
i check my form, the Grid X & Y are already set as 24.
Looks to me like the bottom form is in cm. looks to me like your windows regional settings have changed. It is not a setting in access.
It may just be you have changed language settings to one that uses a metric measurement system rather the US
If you need that language but want the U.S. measurement system go to:
settings>Time & Language>Region>additional date, time and regional settings>change date, time or number formats>additional settings - and change measurement system from Metric to U.S.