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on ipad try to zip the folder with many folders and files to get 2-3 Mb zip-file. and then unzip it.
when i do this i don't receive 2-3 mb zip-file. only 1-1.6. mb zip-file with many files missed.
hm its very strange, cuz i have these problems systematically
I`m trying to modify big project (about 260 files in 66 folders in C-language), archive it and upload to dropbox. But when i archive files, some of those are missed in zip-file (entire folders can be missed).

And another thing. When I archive files a several times in a row, the result archive is empty.

archive files -> send to dropbox;

receive and modify files;

archive files -> there are i get empty archive.