When exporting from a Scroll-Versions managed space, the page tree is created by Scroll Versions. Since this may take quite some time depending on the amount of pages and page restrictions, the default socket timeout of 10 seconds as configured in the Confluence settings is too short.
We should increase this to 120 seconds with an option to override it by the Confluence socket timeout, should the latter be higher.
Open the Confluence Global Administration
Click General Settings scroll all the way down and increase the socket timeout from 10000 milliseconds to 120000 milliseconds (two minutes).