Hi.
I am upgrading LS version 1.91 Build 11379 to 11804, and got below error message.

ComfortUpdate step 4
Error : PCLZIP_ERR_BAD_FORMAT (-10) : Unable to find End of Central Dir Record signature

Anyone know the solution, please help.
Many thanks in advance.

Not sure what might cause the problem but a manual update should do the trick, see docs.limesurvey.org/Upgrading+from+a+pre...tions+for+LimeSurvey

Thanks Mazi, will go thru it ...

You're welcome!

There has been an updater fix recently, not sure if this also solves your problem but it might be worth a try.

I have this problem with a local installation (WAMP) at the moment as well.

From Version 2.00+ Build 130226 to 130305.

Tried it various times and then suddenly it worked. Seems like it was a temporary problem with the update server.

Hi Holch, you are very lucky.
I still got the same error when try to update from v1.92 into v2.0.
Have tried 3 or 4 times, and need to stop since the users start clicking their workstation.

Well, I tried it actually some 10-12 times until it worked.

However, mayor upgrades I usually don't install over the productive installation, but install it in parallel and move everything over there.

Never had any problems with the upgrade on my local machine, but I thing it is just a lot cleaner.