Windows operating system is one of the best operating system in the world. With the help of the Windows OS, you can complete your professional or personal tasks very easily. You can install so many applications on this operating system with the help of the Windows update service. These apps will help you in completing the tasks. But sometimes when you try to open an installed app in the computer then you get Ac1st16.dll not found error in Windows. It is really a very annoying situation that comes to you due to the corruption in the Ac1st16.dll file associated with that application that you want to open. The error is so critical that it can delete many of your important computer data severely. So, it is very essential to fix the issue with the help of the troubleshooting guide stated in this page. You can use Advanced System Repair tool to fix the issue automatically.