Is it possible to install Cygwin on a Windows XP system without having the admin rights?
Run the installer with the
-B command line option:
I think so.
Not being awkward, but, it is simple to try and it will have no negative consequences if you can't.
If for some reason you can't, take a look at this earlier answer - https://superuser.com/questions/229329/gnu-tools-for-windows/229414#229414
You will be able to use some of the features of cygwin without doing an install.
It is possible. When I installed as non-Admin on my XP machines, the installer would ask if i wanted just for me (I did) or for all (where it needed an admin passwd). It can go anywhere on disk (though I'd recommend a folder without spaces in it, since many scripts don't guard against spaces in filepaths) and doesn't have much in the way of registry entries in base install. Some tools like inetd, sshd, and cron will need admin to install the services, but these are less critical.
That said, I haven't tested on Win7 (I now have a Linux desktop, don't need Cygwin).
As someone else said, be careful if you're not authorized for this. There are a lot of tools in corporate environments that look for rogue installs of software. You'll be installing a huge heap of EXEs for them to find.
I have just done it, and it works like a charm. No problems so far with basic tools and X.
The only noticeable problem so far is that the installer complains that it cannot write to the "All Users" start menu, even if I uncheck the option "Make start menu entries" and select "Install only for me".