From one buyer:
You may have heard this from others but on my pc, if I hit the 'click here' link and chose to 'save' the file it didn't work, if I chose to 'open' the file it did work... Weird... but thought it might help you if someone else is having issues. The clitch where there was an error coming up when I tried to open the downloaded and extracted 'goFRUITYourself' file seemed to right itself this 2nd time I downloaded it. Who knows what happened, but it's all good now so, I can't wait to get stuck into your book.
This is from Ejunkie, who I use to sell my ebook through:
Lately we have seen increasing reports and other indications that some nonstandard third-party software can interfere with our download process. These problems generally involve download accelerator/manager software, typically provided as a browser toolbar/extension/add-on, or some types of antivirus software, particularly if it includes a link scanner or other real-time Web browsing protection features.
You can ask affected buyers to temporarily disable such software if they're using any, and then try their download again. If you already scanned the file as virus-free before uploading, you may wish to reassure them of that, and you can recommend that they re-enable their antivirus scanner once the download is complete and, if they wish, scan the downloaded file for viruses before opening it.
Bear in mind that any download can only be as fast and reliable as the slowest, flakiest link in the chain, which is usually the buyer's own computer and ISP connection.
While broadband connection speeds are rated in bps (small-b bits per second), computers typically report download progress in Bps (big-B Bytes per second). At 8 bits per Byte, this means the maximum download rate a buyer sees would be 1/8th their maximum rated connection speed, likely a bit less due to networking overhead, so more like 1/10th in real-world conditions -- e.g., a typical 1.5 Mbps consumer-grade broadband connection could expect to see download transfer rates around 150-180 kBps at best.
There may also be temporary issues with the buyer's ISP or a network routing issue ("Internet traffic jam") anywhere along the route across the Internet between our download server and the buyer's ISP, or their computer could have malware such as a virus that's hogging all the available bandwidth on their connection or causing their computer to misbehave, or other problems may affect the behavior of their computer or connection.
Many consumer-grade ISP connections advertised as "high speed" only provide their maximum rated speed under ideal conditions and/or for brief bursts at the very start of any download connection. This initial-burst speed is suitable to accelerate routine Web browsing, as most Web pages and the images and other content embedded in them are generally rather small files, but larger files would only see that max speed as the download begins, which quickly gets throttled down to a much slower speed as the download size exceeds anything that would normally be viewed as part of a Web page.