When you "opened" the first file - 7-zip probably combined.
Put all splits in one directory,
highlight the first split (filename.001) in 7-Zip File Manager,
now the File > Combine files... feature is available and functions.
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I opened the first file in 7-zip but the "combine" selection was greyed out. Could not open second zip file at all.
Could someone give me some info on how to split zip files and then combine them?
Thanks.
When you "opened" the first file - 7-zip probably combined.
Put all splits in one directory,
highlight the first split (filename.001) in 7-Zip File Manager,
now the File > Combine files... feature is available and functions.
This caught me out too. In 7z, navigate out to the folder containing the multipartites and the combine is active.