It is possible by installing a printer, even if only virtual, that can do DIN A1 or by creating a user-defined page layout.
In Excel itself, (as far as I know) there are no setting options for this.
If you want to print it as A1, you could print / save it in PDF file and then print it to the plotter as A1 using PDF Creator. This is intended as a detour solution. From this moment on, Excel is logically out ...
Or print out A1-sized posters in 4x A3 formats, if the printer can only print until then. In the printer's own settings; look for any poster option for dismantling, if available. Alternatively, look for freeware software for posters and print from them. Take a Look at the Windows Shop.
I would be happy to know if I could help.
I know I don't know anything (Socrates)
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