dragonoid,
1) First of all, make absolutely sure you do all the following stuff with a Windows account which has Administrative privileges.
2) Register msxml3.dll again:
Click Start > Run and then type:
regsvr32 %windir%\system32\msxml3.dll
You should see "DllRegisterServer successfully registered" or the likes.
3) If that didn't work (but make absolutely sure you executed the correct command in the correct way), then first check out the following KB article if the registering error you got in step 1 is the one described there:
http://support.microsoft.com/kb/932628.
If so, follow the steps given there.
If it is not, then you should proceed with re-installing MSXML 3 again. However, here is a catch 22... Every link pointing to the MSXML 3 download gives a 404-error!!! Doh!
So, instead you could maybe try to (re-)install MSXML 4. Though I'm not sure if that would fix anything since these kind of libraries are not always updates of a previous version. Quite often they are completely different and actually run side-by-side. But trying this can't hurt:
MSXML 4 SP3 and
MSXML 4 SP3 update
(make also sure that you select the proper language before you download stuff from the Download Center)
After installing the above two libraries, it is best to re-check
Windows Update
4) Reboot your computer and try to sign in again in Messenger.
5) If it still doesn't work I strongly suggest to contact the official Windows Live Support, nomatter what you might think of MS.
Explain your problem in detail, starting from that first error you got, the exact steps you did to solve that, and then proceed with explaining this second error you got. Also explain all the steps you did before/above. Eg: explain that you tried to download MSXML 3 but that every available link gives a 404-error (important! they need to know this). And then explain that you tried to install MSXML 4 instead (and also give the download link from where you've downloaded it), including its update (again, give link). Explain after which steps you have rebooted. Etc Etc Etc
All in all, be as descriptive and as detailed as possible. Last tip (which people quite often do wrong): don't use abbreviations for names of programs or libraries either as that can be confusing and even wrong. For example, I know it is convenient to say "WLM" instead of "Windows Live Messenger", but it is very essential that you don't use such abbreviations.
The official forums in regards to Messenger can be found here:
http://windowslivehelp.com/forums.aspx?productid=2
Last important thing: be patient. The people at Windows Live Solution Center get hundreds of questions each day. Also, remember to follow up on questions they might ask and remember that they, at first, will probably give you the same solutions you've already tried. This is normal! Each time an issue/question is posted they need to follow the proper trouble shooting steps to properly diagnose the problem and to properly escalate it. Bare with them and don't give up.
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quote:
Originally posted by Arcticwolfx
I do agree with you on that Microsoft's given answers to problems are usually rather useless and often don't even really refer to the problem itself.. Wonder if (some of) those answers are automated replies with a smart scanner.
I beg to differ in many, but not all, cases. I think "usually rather useless" is seriously exaggerated, because:
Quite a lot of their solutions are real working solutions. I hate to say it but often the reason why some solutions seem vague and/or don't work is because people don't always give the proper full details or explain their problem correctly or dismiss whatever MS says/suggests because "they suck anyways".
A quick view on the Windows Live Solution Center clearly show this. The amount of threads with biased and half-arsed explainations are countless. This said, there are also quite often issues and problems which seem the same but need a completely different solution, or vice versa. Note that many solutions given on this forum, for example, came directly from research based upon MS forums and/or are direct 'MS solutions'.
And then there are also problems which mask other problems. Fixing the first thing and you'll notice another error, and too often people then quickly come to the (wrong) conclussion that MS' solution didn't work. While in fact they did work, but there were other problems underneath it which need other solutions.
Don't get me wrong though, there are indeed some crappy solutions out there. But at the same time, there are also quite a lot of very good and working solutions given by them, if you follow them properly and with common sense.
Note: no, they do not use a 'smart scanner'. They are real people... but like every other big and professional support center they do use standarized replies (especially as first replies). Which is very common and logic seeing the shear amount of (repeated) questions they get on a daily basis. If those replies don't work for you, you only need to reply back (in a proper way) why they didn't work and they will escalate the issue further.
/ 
