I'm installing .NET 3.5 SP1 using the file 'dotnetfx351.exe' with a file size of 237054 KB. This is the full installed that does not need to access the net as I can install this on a machine that has not network plugged in.

My question is, why is this so very slow when I install it on a Panasonic CF-19 'Toughbook'. This machine has no network connected, and when I run the installer it says that it needs to download 297MB. It then proceeds to the download screen and downloads 10MB, then timeouts 5 times, and downloads another 10MB, and so on until it has downloaded the whole thing. This takes over an hour, and obviously, doesn't actually download anything.

On other machines, also not networked, this 'downloading' takes about 10 seconds, and it normally only says that it needs to download 10MB.

I presume it has something to do with how the machine is configured. But I have no idea where to start looking.

There are two things I find confusing: 1/ Why does it say it needs to download 297MB, when on other machines it says 10MB? 2/ Why does it take so long, and need to timeout, when all the files are on the install media?

What I want, is a fast install on this machine.

Some more information which probably doesn't help. The machine comes with a UK keyboard but is configured to be 'English (US)'. This makes me think it's a language setting issue, but really I think it's a red herring.

migrated from stackoverflow.com Aug 20 '09 at 0:20

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  • This question doesn't appear to be programming related, and is probably a better fit for SuperUser.com – bdukes Aug 19 '09 at 3:57
  • .NET 3.5 is definitely not 10MB :P – Thorarin Aug 19 '09 at 5:16
  • @Thorarin: It can be 10MB if you already have some .NET framework components installed. See smallestdotnet.com – Grant Wagner Aug 19 '09 at 17:05
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    Why is it so slow? Because Microsoft has made the installer. If you've tried installing Visual Studio, SQL Server or pretty much any other Microsoft product in the last few years, you might start to notice a certain trend. Installing Microsoft software is slow. – jalf Aug 19 '09 at 17:09

The 10Mb download is a red herring. There is nothing to download, it's all contained in the install already. I just 'says' that it needs to download some data.

On the system where it's fast it says 10MB, on the system where it's slow it's 297MB.

I've found the solution: How can I install .NET framework 3.5 on XP machines without internet connection?

It had to do with the fact that the machine came from the UK, and was (I guess) trying to download a language pack (and failing very slowly).


You may want to check out SmallestDotNet:

If your users have internet connectivity, the .NET Framework is only between 10 and 60 megs. Why such a wide range? Well, it depends on if they already have some version of .NET. If you point your users to the online setup for the .NET Framework 3.5 SP1, that 2.8 meg download will automatically detect and download the smallest archive possible to get the job done.


Sounds like some of your systems got the redist and some got the web installer. Make sure you're using the redist on all of them.


Do you have Windows Installer 3.1 installed on the machine? That is the only prerequisite for the .NET installer, and would probably explain the small 10 MB download on the connected machines.

I have used the installer you mention in the post on similar Toughbook notebooks running XP Pro to install the .NET Framework 3.5, and have not experienced any problems.

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