Cannot start LibreOffice after Portable Apps updated me to 4.1.2

I had Libre Office 4.1.1 or something like that and Portable Apps platform showed me that a new version 4.1.2 was available. I let Portable Apps update me and all of the apps with Libre Office show this message when I try to start them:
QUOTE
The program cannot be started.
The service manager is not available.
("Cannot open directory file:///E:/PortableApps/LibreOfficePortable/App/libreoffice/program/services")
Start setup application to repair the installation from CD, or the folder containing the installation packages.
UNQUOTE

I do not want to remove and re-install because I presume I will lose my addin (whose name I have forgotten!) and other settings.

How do I resolve this issue?

(10 minutes later I edited this:
I am using Windows 7 and have used Libre Office from this memory stick for a year or two with no problems, always updating to the latest version.

I have just installed a fresh copy of Libre Office (it turns out to be 4.1.2.3) on a memory stick with Portable Apps, but that had no previous version of Libre Office. It works fine.)

Edited 19 Oct. The software runs fine if I click on the executable, which is two folders deep on the memory stick. However, I always have a shortcut to the executable in the root folder. It fails, as described above, when running from the shortcut. It works fine when run from the executable directly.