Update error

I can not update from Version 1.0.9b2 to 1.1

Downloading update from https://premium.wpmudev.org/wdp-un.php?action=download&key=<thekey>&pid=168…

Unpacking the update…

The package could not be installed. PCLZIP_ERR_BAD_FORMAT (-10) : Unable to find End of Central Dir Record signature

Please advise,

Thanks