Apple launched iOS 9 for iPhones, iPads and iPod Touch device in full glory but failed to process a smooth installation. The roll-out of the latest software began on Wednesday all around the world. Shortly after the devices started receiving the update alert, users tried to proceed as norm, but encountered multiple issues, which have been reported on Apple Support forum, publication forums and even on Twitter.

This is certainly not a great start, which is reminding users of the painful experience with last year's iOS 8. The most common error found during iOS 9 install is "Software update failed. An error occurred downloading iOS 9." The error is likely a cause of busy servers that are unable to handle the traffic as fans rush to install the free software at the earliest hour.

"Three separate devices, all eligible for iOS 9, say the update is available. I'm on wireless, click the download and install and agree to the terms of service. Then a window pops up and says "Software Update Failed – an error occurred downloading iOS 9 (btw, got plenty of space on all devices). Even tried on a different wireless provider," a user complained on Apple's Support forum on Wednesday.

Besides the update failure, some users have also reported being stuck at the "Update Requested" screen. Other problems have also been reported by users MacRumors forums, who are complaining slow downloads, Wi-Fi drops, hidden Airplane mode toggles among other bugs, IBTimes reports. Twitter was flooded with complaints on the iOS 9 downloads.

Apple iOS 9 underwent nearly 100 days of testing under the beta programme. These issues are setting off users. Apple hasn't released an official statement on the matter but there are some workarounds to get the installation going.

The high traffic on Apple's servers is probably causing most of the download problems, hence it is better to wait for a few hours, or two-three days. You can also try downloading the iOS 9 update via iTunes by connecting your iDevice to a PC. In case you are not familiar with this method, follow out step-by-step guide to walk you through the process.