I have done many, a few things to consider I have E-designer & it will run on Win11 (providing you have the USB converter with the latest FTDI chip).
Have you created an empty project as the E100 ?
You may need to change the default communication as it is possible that this has been configured differently goto transfer then communication properties & the default should be 9600, Even, 7, 1 But if someone has changed this then you may have to try all options (I cannot remember if dip switch 1 is to boot into transfer mode but it is worth a try, this If I remember corrctly does give you information on it's configuration). Note: I did notice on some panels that the dip switch was upside down so it was dip switch 8 only ever did a few 100's but many 1060-1100 so not sure if the 100 has the dip switch. also, I have a funny feeling the 100 may not have a seperate supply or it is a 5v, however, again my memory is not that good & I think some used the 422 cable connected to the PLC as the power source so only needed the 5v if not connected to the plc.
Also if it has been password protected then you will not be able to upload the project it will ask for the password.
I also remember that there were two types of cable, the original was for the older MAC terminals (the original before the E series), this cable had the RX/TX swapped over, came across this once, I had the correct cable for the Mac series, tried to use it on the E series had the same problem, got some drawings from Beijers (made by them & re-badged for Mitsubishi), turns out the old mac cable & the new e series had those swapped over.