on my notebook with windows11 have repeated problems uploading sketch to Arduino mega 2560 !
with Win7 on my PC it works every time (just as it does with A.nano on all my computers).
file ch340 is available as driver.
depending on upgrade version of windows11 loading sketch works or works Not !
its too depending of A.mega board : with the board from Joy-IT it works more often..
thats exciting because every time win11 gets an update the problem apears again..
think, if i cant find any reason or solution
will change to A.nano at all places where i have A.mega now
and use with expanders..