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I have some files that have .gid extension. What Mac software should I use to open it?

I use OS X 10.5.8.

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Do you know what kind of files they are? (Any information would be helpful.) – CajunLuke Oct 14 '11 at 22:07 Is it this file extension ? – Kassym Dorsel Oct 14 '11 at 22:12
@CajunLuke I don't know but when I opened a link from KassymDorsel I just knew it's a Windows file, I got it from a laptop that has Windows OS in it. I thought it's like CHM file, could be opened in Mac :-/ – Arie Oct 15 '11 at 6:20
up vote 3 down vote accepted

It could be a Windows global index file (.gid) or something else completely different depending on where it originated from. If indeed it is the common Windows type, it's used basically tell Microsoft help documents where to position the window on the screen, not much more.

  • If you want to open it Control mouse-click > Open with... > Text edit

It might be gibberish or it might not; either way you could take a look if you're completely curious. Sometimes unknowingly, mistakenly, or haphazardly, software developers will use .(lll) whatever in relation to the software they've created while another application or computing platform also uses that extension; this can result in confusion, problems and conflicts.

Take a look at this document which lists the most commonly used extensions.

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Right, I think this gid file is an accompany of HLP file. I tried your answer on this gid file and it opened a kind of explanation of one file, then I tried to open the HLP file, I can read text inside it, although gibberish, it worked. – Arie Oct 15 '11 at 6:22

The .gid extension is most commonly associated with Microsoft Windows help file indexes, although any program could create a file with any extension.

Just because a file is on your computer, it does not follow that the file should be opened by the user at all.

Another kind of file that sometimes has a .gid extension is a file containing geometric information data. It appears to be a format for specialized technical engineering data.

With more information about how you came across this file, one might be able to provide a more useful explanation.

Finally, it is worth noting that attempting to open the file in a program like TextWrangler or HexFiend could help you figure out if the file contains human readable information.

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