How do I decompress the files I download from your site?

Our files are compressed using WinZip and have the .zip file suffix. Users who download compressed files will have to decompress the files before using them.


Windows XP has a built-in decompression tool that decompresses .zip files. Users with other Windows versions may need to download the utility from the WinZip website.

WinZip and the Saved Files Utility

WinZip users (and those who use the built-in decompression tool in Windows XP), should be aware that WinZip has two ways to extract files: by using drag-and-drop and by choosing "Extract" from underneath the "Actions" menu. These two methods produce different results. If you use drag-and-drop, then you will only get the files...not the folders that enclose them. Hence you'll lose the hierarchy that we've set up (including folders that are titled with study names and dataset names). If you use the "Extract" command from the "Actions" menu, then the folder hierarchy is preserved if 'Use Folder Names' is specified in the extraction dialog box.

When I attempt to uncompress the files I downloaded from your site, WinZip complains that the file name is insensible. How can I uncompress the file?

The total path length (not file name length) has to be less than 255 characters. Our file names can be lengthy. If the path to which you wish to extract your files is also lengthy, then WinZip will fail.

Extract your files to the root directory of your hard drive. I.e., extract the files to c:/ instead of c:/User/My Documents/Various Social Science Projects On Which I Work/ICPSR Data/.


For Macintosh OSX users, decompression software is built into the operating system; you can open compressed files by double-clicking on the .zip file.

If you're encountering problems with the MacOSX built-in decompression software, you may wish to download WinZip for Mac.


Users in the UNIX/Linux environment can simply use the unzip command to decompress .zip files.

Once you have the appropriate software on your local machine, follow the instructions supplied by your software to decompress the zipped files.