Software & Apps Windows How to Fix Ac1st16.dll Not Found or Missing Errors A Troubleshooting Guide for Ac1st16.dll Errors Share Pin Email Print Ac1st16.dll Error Message. Windows The Ultimate Laptop Buying Guide By Tim Fisher General Manager, VP, Lifewire.com Tim Fisher has 30+ years' professional technology support experience. He writes troubleshooting content and is the General Manager of Lifewire. our editorial process Facebook Twitter LinkedIn Tim Fisher Updated February 21, 2019 Ac1st16.dll errors are caused by situations that lead to the removal or corruption of the ac1st16 DLL file. In some cases, ac1st16.dll errors could indicate a registry problem, a virus or malware issue, or even a hardware failure. There are several different ways that ac1st16.dll errors can show up on your computer. Here are some of the more common ways that you might see ac1st16.dll errors. Ac1st16.dll Not FoundThis application failed to start because ac1st16.dll was not found. Re-installing the application may fix this problemCannot find [PATH]\ac1st16.dllThe file ac1st16.dll is missingCannot start [APPLICATION]. A required component is missing: ac1st16.dll. Please install [APPLICATION] again The context of the ac1st16.dll error is an important piece of information that will be helpful while solving the problem. Ac1st16.dll error messages might appear while using or installing certain programs, when Windows starts or shuts down, or maybe even during a Windows installation. The ac1st16.dll error message could apply to any program or system that might utilize the file on any of Microsoft's operating systems including Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, and Windows 2000. How to Fix Ac1st16.dll Errors Do not download ac1st16.dll from a "DLL download" website. There are many reasons why downloading a DLL file is a bad idea. If you need a copy of ac1st16.dll, it's best to obtain it from its original, legitimate source. Start Windows in Safe Mode to complete any of the following steps if you're unable to access Windows normally due to the ac1st16.dll error. Restore ac1st16.dll from the Recycle Bin. The easiest possible cause of a "missing" ac1st16.dll file is that you've mistakenly deleted it.If you suspect that you've accidentally deleted ac1st16.dll but you've already emptied the Recycle Bin, you may be able to recover ac1st16.dll with a free file recovery program.Recovering a deleted copy of ac1st16.dll with a file recovery program is a smart idea only if you're confident you've deleted the file yourself and that it was working properly before you did that.Reinstall the program that uses the ac1st16.dll file. If the ac1st16.dll DLL error occurs when you use a particular program, reinstalling the program should replace the file.The ac1st16.dll file is most likely related to an older version of an Autodesk program, DWG TrueView and AutoCAD being two examples. However, your particular DLL file might be used with some other kind of software.Try your best to complete this step. Reinstalling the program that provides the ac1st16.dll file, if possible, is a likely solution to this DLL error.Run a virus/malware scan of your entire system. Some ac1st16.dll errors could be related to a virus or other malware infection on your computer that has damaged the DLL file. It's even possible that the ac1st16.dll error you're seeing is related to a hostile program that's masquerading as the file.Use System Restore to undo recent system changes. If you suspect that the ac1st16.dll error was caused by a change made to an important file or configuration, a System Restore could solve the problem.Update the drivers for hardware devices that might be related to ac1st16.dll. If, for example, you're receiving a "The file ac1st16.dll is missing" error when you play a 3D video game, try updating the drivers for your video card.The ac1st16.dll file may or may not be related to video cards - this was just an example. The key here is to pay very close attention to the context of the error and troubleshoot accordingly.Roll back a driver to a previously installed version if ac1st16.dll errors began after updating a particular hardware device's driver.Use a free registry cleaner to repair ac1st16.dll related issues in the registry. A free registry cleaner program may be able to help by removing invalid ac1st16.dll registry entries that might be causing the DLL error. Need More Help? If you're not interested in fixing this problem yourself, see How Do I Get My Computer Fixed? for a full list of your support options, plus help with everything along the way like figuring out repair costs, getting your files off, choosing a repair service, and a whole lot more.