[BigZip] The final hash has not been computed error
Forge component by Carlos Alfaro
Application Type
Traditional Web

Hi Kilian,

First here is some general information:
Version: BigZip v2.0, OutSystems 11
Problem occurs since: +- 1 month
Problem occurs just for +- 0,005% of the documents that we unpack

When trying to unpack an encrypted zip file from the Azure Blob Storage by using BigZip, we got this error:

The final hash has not been computed.
at Ionic.Zip.WinZipAesCipherStream.get_FinalAuthentication()
at Ionic.Zip.ZipEntry.VerifyCrcAfterExtract(Int32 actualCrc32)
at Ionic.Zip.ZipEntry.InternalExtract(String baseDir, Stream outstream, String password)
at OutSystems.NssBigZip.ZipHandle.FileExtractM(String fileName)
at OutSystems.NssBigZip.CssBigZip.MssFileGetMemory(Object ssZipHandle, String ssFileName, Byte[]& ssFileContent)
at ssEZIS_AzureCommon.RssExtensionBigZip.MssFileGetMemory(HeContext heContext, Object inParamZipHandle, String inParamFileName, Byte[]& outParamFileContent)

When unpacking these document manually, no problems occurs.

When trying to investigate what goes wrong, we also found another (not OutSystems related) topic on the internet about this problem, which seemed software related.

Could you let us know if this a bug in the component or if something else goes wrong?



Hi Jordy,

It seems a bug in the version of Ionic.Zip that is used. I found a post on the internet (probably the same you found) that describes it's fixed in a later version of DotNetZip, the successor of Ionic.Zip. I published a new Under Development version (2.2.0) which you can find on the versions page that uses the latest DotNetZip. You need to manually install it I think, as it's marked Under Development (I haven't tested it myself yet). Could you please test if this version works for you, and the bug you are experiencing is gone? Thanks in advance!

Hi Kilian,

The version is tested and we are now able to get the files where formerly the error occured, so this new version is the right solution. Thanks for your quick help!


Great, I'll make this Under Development version an official version then. Thanks for testing!

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