>>Hi @all
>>
>>We are generating many ZIP (with Dynazip) Files for Dataexchange. Unfortunately we receive from time to time BAD CRC Erros.
>>
>>How can I detect these Errors without unzipping the File?
>>Any tool out there to programatical (via FoxPro) check the File for these Errors?
>>
>>Any Tipp wanted
>>
>>Grüße
>>Jörg Schneier
>
>Two suggestions. First would be to change over from the no longer supported Dynazip and use http://www.sweetpotatosoftware.com/SPSBlog/PermaLink,guid,b5fdd81c-4d47-469b-acbb-ddda807adacc.aspx
>
>Craig Boyd ZIP stuff works great.
>
>Dynazip has a test switch that will check the integrity of the zip file. However, you might find it easier to use Craig Boyd's program. It will do the same thing in a much simpler way. And yes, it will read zip files created by Dynazip. They all use the same standards.

When I was testing a zipping solution, all zlib and zlib1 based tools have failed when the size of the zip has exceeded some size, about 19 megabytes. As I may have files larger than that, I went for wrapping a DOS-typed tool, pkzip25, in a API_APPRUN call (from late Ed Rauh). Pkzip25 is maybe aged - 14 years now - but it still works without a hitch.