How to open .ISTR files on Windows
To open .ISTR files on Windows, install and open IsoStar (CCDC).
Step-by-step instructions
- Install and open IsoStar (CCDC).
- In IsoStar, use File/Open (or the equivalent) and select the .ISTR file; or double-click the file and choose IsoStar if Windows prompts you to select an app.
Common issues
The .ISTR file opens as text in a web browser
This commonly happens when the server sends the wrong MIME type, so the browser treats the content as plain text instead of an IsoStar file.
- Configure the web server to serve .istr as chemical/x-isostar (CCDC support provides an Apache mime.types-style mapping: chemical/x-isostar istr).
- After fixing the server, download/open the file again and open it in IsoStar.
No app is associated with .ISTR (double-click does nothing useful)
Your operating system may not know that .ISTR corresponds to IsoStar data, or IsoStar is not installed.
- Install IsoStar and then use “Open with…” to select IsoStar for .ISTR files.
- On Linux desktops, ensure your shared-mime-info database is up to date so *.istr can be recognized as chemical/x-isostar.
The file won’t open or appears corrupted in IsoStar
The file may be incomplete (failed download/transfer) or not actually an IsoStar .ISTR file.
- Re-download or re-copy the file from the source and compare sizes if possible.
- Confirm with the sender/source system that the file is an IsoStar scatterplot/data export intended for IsoStar.
Security note
.ISTR is not a general-purpose “archive” you should unpack with random tools; treat it as application-specific data intended for IsoStar.