Zip-compression-zip64 question

Hi there,

Sorry if this is a silly question, but I’m having problems with the zip-compression-zip64 option.
A particular backup fails while trying to write the file list (millions of files …) stating that the zip64 option is not set.

To fix this I am trying to use the zip-compression-zip64 option but for some reason this is not successful and the backup fails with the same message.

Could someone confirm how this needs to be set? I have used --zip-compression-zip64 = True
If this correct? How can I verify that the option has been enabled successfully?

Many thanks.

Welcome to the forum @Dominic-Schaefer

Where was that used? Is this backup on the command line (e.g. Command Prompt, Linux shell, etc.)?

If something changed, that would do it. There’s nothing that specifically tells you what options you input.

If this is on command line, please try removing the spaces around the = sign. They may confuse things, however typically just using the option name (which you did) implicitly makes it true, but maybe not here.

Many thanks, @ts678

Sorry for the omission. I am using FreeBSD 12.2 and this is used as a command line option in the rc.d script that starts the service.

Ok, since the backup to test this with takes 1.5 days I was hoping for another way :wink:

I checked my command line option and it does not have any spaces around the =.

I assume there is no way to provide this option via the GUI?

For a GUI job, add it here:


and get:default option value


and check it to turn it on. GUI doesn’t affect CLI, and I don’t know why your CLI option wasn’t working.

Zip-compression-zip64 clarification made me suspect Duplicati sets zip64 just-in-case, if configured.

Opening a sample tiny dlist file in 7-zip and viewing Properties of filelist.json confirms this is the case:


A different sample tiny dlist without GUI option set did not have that, so there’s one way you can test…

Thanks a lot @ts678 , that did it!

I couldn’t find the GUI option (looked in the wrong place) and therefore was trying to use the command line option. No idea why that didn’t work but the GUI option does.

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