Update fails

I am trying to update from version 2.5.8 to 2.5.9 invoking from plugins page but it fails after unpacking the ZIP file – simply stops. The second method through WordPress Update page stays showing wait cursor endlessly. I am in the phase of constructing a new website on localhost using Hotec theme and apart from Wysija a.o. the plugins Polylang, LayerSlider WP and Revolution Slider. Any advise would be appreciated.

https://www.ads-software.com/plugins/wysija-newsletters/