I manage a Windows VPS on hosteurope.de. I've been trying to update it to SP1 - it says Windows Update are disable by group policy, and workarounds found online don't seem to work - same thing for downloading and attempting the install of the offline SP1 installer.
It seems that (just discovered), "No Microsoft updates, including service packs, can be installed inside containers" and this is a limitation of the Parallels software (Parallels article ID 11153)
The OS interface was originally in German and "Not all Windows 2008 R2 SP1 editions and locales are supported by Parallels Virtuozzo Containers for Windows" - that may be the reason why SP1 was not applied yet.
Updates and fixes released by Microsoft are otherwise (seemingly) regularly applied, the last one applied being KB2809289 on 4/4 - so it's, apparently, mostly a matter of SP1 not being applied. Can the OS be considered up-to-date? The computer it is being used for hosting several websites, in their public/production form.
How unsafe and acceptable is this practice, in this particular context?