Update: For Windows XP users it doesn't matter what you do, Live Sync is dead. I am now using Drop Box which isn't quite the same but seems to fulfil my current needs. Now even though I am a complete stranger, if you e-mail me (use the link down the left column) I will try to send you an invite to join Drop Box which gets you and me some extra free space.
I got a message from Microsoft yesterday telling me that Windows Live Sync would soon stop working, but that if I just followed the attached link here it would take me to a page that would address my problems.
Well, it didn't, because I am using Windows XP, not 7 or Vista (cough, spit!). So I had to follow another link to Windows Live Essentials where I could download an installer that would update Windows Messenger (which I don't use) and add other bits that will hopefully allow me to go on using Live Sync (which I use to back up and copy files automatically from my laptop to my desktop and vice versa).
The only trouble was that the updater refused to install the programs. Instead, I kept getting the error message above and something about a problem with "messenger.msi" in the C:\Windows\Installer" folder. It also suggested there might be a problem with a conflicting program.
There followed the usual two hours of frustration trying to find an online solution, disable conflicting programs, etc, etc, etc.
Finally, this combination seemed to fix the problem:
1. First, I discovered there was no messenger.msi file in the C:\WINDOWS\Installer folder.
2. I used 'Search' and found several copies in other temporary folders.
3. I copied one of these to the C:\WINDOWS\Installer folder.
4. I started Windows Messenger, which I hadn't used for ages, and logged in.
5. When I logged in, it told me there was a new version available and I clicked the necessary to start the download and installation.
6. This seemed to take me to a screen identical to the Windows Installer screen that wasn't working earlier.
7. The installation began, but seemed to hang after several minutes.
8. I left it to get on with it, but after about quarter of an hour shut the thing down manually.
9. I went back and tried the original Windows Installer again.
10. This time it told me that I'd already got Windows Messenger installed, and it didn't need updating (which it had done before).
11. The rest of the installation went OK.
So the problem seems to be something to do with (a) not having the messenger.msi file in the Installer folder and (b) perhaps not updating Windows Messenger first.
Anyway, this worked for me, I offer it to those experiencing the same problem.
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