I have exactly the same issue. 3 days ago, I was trying to update ESPN Scorecenter. It started downloading in iTunes then an error showed up (err=8008). Now, this error will show up everytime I connect my iphone to my computer...so annoying
Tried searching for iTunes download folder but nowhere to find it....
That is interesting because I have the same app giving me problems on my iPod Touch. I'm getting the errors from Urbanspoon and ESPN Scorecenter.
I can download the apps no problem directly from my Touch and transfer them to my computer, but I still have the errors. Have yet to see or find a solution that works.
I have tried many ways and finally got a solution. It worked for me when I tried this:
1. I uninstalled iTunes from my laptop and also deleted iTunes folder
2. Installed iTunes on another computer. Then signed in my apple id and checked for available download.
3. The app with download error (8008), which is ESPN Scorecenter for my case, started downloading normally without error.
4. Then I connected my iPhone to sync with the iTunes on this computer.
5. Went back to my laptop and Installed iTunes, signed in with my apple id then checked for available download......and no more download error.
This one had been bugging me every time I launched iTunes for a week. The "failed download" in question was PCalc in my case, a calculator… makes "8008" all the more amusing.
Anyway, what finally worked was running iTunes on another Mac, signing in with my store account there, and doing a Check for Available Downloads from that second computer. PCalc duly downloaded – an 8 megabyte download instead of the faulty 1 KILObyte one on my own Mac's copy of iTunes – and cleared the issue on Apple's end. When I went back to my machine and restarted iTunes I was finally free from the nag screen.
Searched far and wide to resolve this issue, tried all of the above and solutions from other threads.
Turned out to be the fact that I use OpenDNS and "Web Content Filtering" that was obviously triggering when I attempted to download applications from iTunes.
To resolve I "Never Block" the following domains in the OpenDNS control panel:
"apple.com" and "akadns.net"
This resolved the issue. You may need to restart your PC after this and wait a few minutes (or ipconfig /flushdns & restart iTunes)