Mixed lowercase and case-preserved folder names

Hi ciobi,

This bug affects only directory trees existing for a while. A new (relatively) directory tree isn't getting affected. So, a workaround could be moving affected trees in new directory, which serves as a alternative root. Let say, you have folders 'Folder1', 'Folder2', 'Folder3' and 'Folder4' inside your Dropbox account. Discussed trouble appear for 'Folder2' and 'Folder3'. You can create in your account a folder 'AltRoot', for example, and move 'Folder2' and 'Folder3' into just created folder. After that you should be able download compressed folders without issues (properly formatted), either the moved folder itself of others contained inside.

Hope this helps to some extent.

Hi Walter,

The issue comes from the fact that for some folders when declared in the zip file they appear with correct capitalization, but when used as part of path to some file inside, they appear entirely lower case. Capitalization mismatch confuses some applications. You wouldn't be able reproduce that because new directory trees aren't affected. I tried to make a list of steps to reproduce the situation for you, but unsuccessfully. If I have to bet, some system upgrade of the web interface seems done wrong. Probably incompatibility with some previously used format (or least not full compatibility). I'm not sure actually. From technical point of view, it isn't mandatory letter capitalizations of directory definitions to match their usage in file paths. This is not clearly defined in ZIP specification, unfortunately. Anyway, all native zippers on either Mac, Linux or Windows, when create a directory trees in a zip file, capitalizations for directory definitions match to those used file path! In some specific cases this is NOT true for the zip algorithm used in Dropbox Web. This is strange, at least, although not technically bug! All applications relying on 'zlib' to access the files, could fall in confusion.

The good in all of this is that Dropbox applications, either desktop or mobile aren't affected, only Dropbox website behave stupid in such situation.

For additional clarity (let's hope) follows a picture of binary view of zipped folder, named "GolfP" downloaded from the Dropbox site:

As could be seen directory definition uses proper capitalization, but when used as a part from the path to file "SamChip.h" all letters are lowercase. The same file produce following view in an archiver:

As could be seen, actual tree starts with lowercase name folder. The properly named folder is empty!

Hope this could gives some directions. Not perfect, but... let's hope experts (at least more experienced) from development team will get right direction.