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Is there a way, on Windows 7, to update a file inside an ISO?

Right now I extract all the files, update the file, then re-create the ISO.

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migrated from stackoverflow.com Jul 19 '10 at 0:34

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I see this question was migrated. Did you ever want to do this programmatically? –  djechelon Oct 28 '14 at 11:28

3 Answers 3

It must be said that the ISO file system format does not support the concept of rewriting or inline-modification. So even if you find an utility (like UltraIso, a shareware utility) that enables you to modify an ISO with a drag&drop style, it will ultimately rebuild the ISO to a temporary file and write it back to the original file.

ISO is meant for non-rewritable optical media like CD,DVD or BD-ROM. All files are consistent and allocated in contiguous spaces. In order to explain what you cannot with ISO, let me tell you what you can with regular hard disk drives and UDF file system (used by rewritable media). A normal hard disk's file system supports the concept of file fragmentation to allow a file that is larger the size of the largest continuous block to be stored in non-contiguous blocks. This feature exists because a hard disk, during normal operation, continuously writes new data and erases old data.

ISO doesn't simply support that.

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Though I have no reason to specify, let me say I'm not affiliated with UltraIso –  djechelon Oct 28 '14 at 11:27

ISO Master is now available for Windows. It doesn't quite do what you ask, but it skips the extraction part.

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http://www.poweriso.com/ is a cheap software that will let you do it.

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