The download files are WinRAR self-extracting Archives. I posted a description of these on a forum post several weeks back:
If you are having trouble downloading the files try an alternative. On the download web page you will have two (assuming you have not modified preferences) download options for each file. There is also a convenient feature to download all files from the page. The two download methods here are Browser Download and Download Manager which uses the Akamai download accelerator. Try the Download Manager links first. If you have trouble then use the Browser Download links.
Tip: Try using Firefox which has a Download Manager built in. Many customers are using this and reporting success. I have tested it myself by downloading the AutoCAD 2011 x64 Archive.
When is the error happening? When the archive is extracting, when the installer is initializing, or somewhere after the installer starts? Can you provide a screen shot?Douglas Lauritsen, Autodesk Product Support
I am unable even to download the akamai net session interface. i keep getting an error message before download completion of the "TCP Port 9421 closed or being used". i use firefox. sorry i'm not that computer savy. any help is very much appreciated.
I am also having issues with the extraction of the zip file.
I tried using the download manager initially but this stalled straight away so it may be a port issue. I then tried the browser download using both Firefox and Internet Explorer and both with exactly the same results.
I have included a screen shot of the error I get.
One other thing is that we cannot access the online help...again I think it may be the proxy server blocking it. What ports does this use?
Any help would be appreciated.
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