Plesk Updater broken in 7.5

[spauldingsmails]

We have recently upgraded to 7.5 Reloaded but when I click on Updater in the Plesk web control panel the following error appears at the top;

Error: File download failed. socket error: 111.

Nothing appears after that except for a Preferences link.

I have checked the logs but am unable to trace the source of the problem, although I may be checking the wrong logs (I am maintaining a linux server for someone and this is the first time I've had to use plesk).

Any help would be much appreciated.