WinZip demo is a free download.
Windows XP has a built in unzip utility, just right click and choose to open it.
7zip can unzip many comrpessed formats by just right clicking on the folder and choosing 'extract files...'
it's free so google it.
this is how i install aircraft and it works fine:
https://forum.flyawaysimulation.com/forum/topic/22935/okso-i-downloaded-some-planes-for-my-fs-how-to-access/
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