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ClamWin won't start - filename CASE problem (solution)

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kethd
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ClamWin won't start - filename CASE problem (solution)

When portable software files are moved between computers, the case of the filenames may get changed, for example from "lib" to "LIB". For some portableapps packages, such as ClamWin and Nvu, this will keep the packages from working properly.

In the case of ClamWin, the symptom of this problem is that the portable-apps package splash screen appears promptly, and then the executable tries to launch but immediately vanishes; there is no visible activity after the splash screen.

A log file CLAMWIN.EXE.log is created in ClamWinPortable\App\CLAMWIN\BIN that reads:

	Traceback (most recent call last):
	  File "ClamWin.py", line 26, in ?
	zipimport.ZipImportError: can't decompress data; zlib not available

The way to spot the problem is that folders that should have all-lowercase names such as "bin" and "lib" are incorrectly named BIN and LIB. And half of the filenames in LIB (the short ones) are all-uppercase; they should all be all-lowercase.

The solution to the problem is to either regenerate the portable package locally, from the single package-install file. Or move the installed package around inside of an archive format that will fully protect the filenames (sounds inconvenient).

The cause of the problem has to do with DOS 8.3 / LFN complications. Short filenames that have mixed case, such as "App", require a LFN name. But short simple filenames like "lib" might get a simple DOS 8.3 representation, which is technically caseless, so when it is tranferred to another computer it is somewhat up in the air whether it is treated as lowercase or uppercase.

The way to design around the problem would be to either use all mixed case folder and file names, to force LFN, or use software that completely ignores case in path and file names. Or maybe avoid Windows FAT entirely... There is a good rant on the subject here: http://www.cocoadev.com/index.pl?MSDOSFileSystem.

In my case, the problem occurs when I use my Creative MuVo to transfer files from XP to 98. So perhaps this problem only occurs on Windows 95/98/ME systems? Can anyone tell me more about the exact cause, and good fixes, if any?

(Note to portable-apps package designers -- maybe it would be fairly simple to add code to the package launcher that would detect that the package had gotten munged up this way, and give a user-friendly error msg about the problem?)

John T. Haller
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Multipostings Deleted / Copying / Unlikely Changes

First, please refrain from multi-posting even if your post applies to multiple products. Multi-posting merely clutters up the forums. People will find it just as easily by searching. Your two additional comments reviving 4-month old topics have been removed as well.

Second, I think this issue only occurs when you're copying files back and forth to a 9x machine, which isn't normal usage. If you simply run this from your portable device, it'll just work. If this isn't the case, please let me know.

Third, the issue is within the applications themselves (Nvu, ClamWin) not within the portable launchers. These issues will likely NOT be fixed by the application developers due to the fact the Windows 9x support is going away in the near future for any of these apps. While they won't specifically remove support for Win9x, they're highly unlikely to do extra work just to get around specific issues within Win9x.

Fourth, attempting to keep track of all the directories and whether their case is correct in the launcher is a bit unrealistic. Nvu Portable has 49 folders within it. Checking them all on launch would slow the whole product down.

Sometimes, the impossible can become possible, if you're awesome!

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