After SP1 update - black screen with mouse cursor

As per title - I decided to update my Win 7 ultimate to SP1 which installed ok but I ended up with a black screen with working mouse cursor and a message box showing something like - "configuring user settings".

This stayed like this for a long time and in the meantime I used CTRL_ALT_DEL to try to run Firefox to get on to the net. Firefox failed to open which appeared to indicate something network related.

I finally shutdown via the taskmanager and booted to Safe mode - with networking. Trying to open a browser resulted in a painful wait which I gave up on. It appeared that it couldn't download anything.

I then did a system restore and got back to full working system. My Windows 7 has been extremely stable and I've no problems. I did a virus check and loaded the update readiness tool but haven't tried SP1 again.

I decided to search around but really this kind of issue seems like it could be caused by a lot of things and I've no clear answer to what is my specific issue. Given the problems with networking issues (eg. some people had suggested they unplugged the LAN cable as their Qnap nas was the problem - beats me but I have a Qnap), maybe it is this.

I doubt it's graphics although originally I suspected it but I do have the latest drivers installed and now I'm back after system restore this is stable as ever.

I'm really searching for either:

1) the best (quickest) way to troubleshoot this problem
or
2) a way to update to SP1 bit by bit - if that's possible. I might be able to find the module responsible then.

Any ideas would be appreciated. Till then I'll stick with my non-SP1 stable system

Why would you install Windows 7 without SP-1?
Where did you get your copy of Windows 7 Ultimate?
With SP-1 installed you will still have over 200 more updates.

If your copy is from MSDN I would suggest checking with Microsoft. I believe they have changed some of the rules about using MSDN products.

What I meant was simple.
Because you have a 6 year old MSDN product that you haven't used in a long time the rules about how it can be use in 2016 might of changed and causing you your problem.
In 2015 Microsoft changed a lot of rules about the use of MSDN.

Could you tell us how you solved your problem. It may help others.

I have no idea what you are getting all huffy puffy about.

I thought you might of got caught in one of the Microsoft rules and didn't know it.
Because you installed it back in 2010. It was just a suggestion on my part to take a look and see if Microsoft still was on your side. If one forget to install SP-1 for 6 years their is a possibility one might forget the rules. That is all I wanted to bring to your attentions.

The good new is we now know Zone Alarm was your problem.
That will surly help somebody.
If your system activated with no problem then that is a good indication Microsoft is happy.

Happy computing.

https://technet.microsoft.com/en-us/.../cc294422.aspx

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