Software & Apps Windows How to Fix Avcodec.dll Not Found or Missing Errors A troubleshooting guide for avcodec.dll errors 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 on March 27, 2020 Windows The Ultimate Laptop Buying Guide Tweet Share Email Avcodec.dll errors are caused by situations that lead to the removal or corruption of the avcodec DLL file. In some cases, avcodec.dll errors could indicate a registry problem, a virus or malware issue, or even a hardware failure. The avcodec.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. Avcodec.dll Errors There are several different ways that avcodec.dll errors can show up on your computer. Here are some of the more common ways that you might see avcodec.dll errors: Avcodec.dll Not FoundThis application failed to start because avcodec.dll was not found. Re-installing the application may fix this problem.Cannot find [PATH]\avcodec.dllThe file avcodec.dll is missing.Cannot start [APPLICATION]. A required component is missing: avcodec.dll. Please install [APPLICATION] again. Avcodec.dll error messages usually appear only while using or installing certain programs. Software from DVDFab, AlienDVR, ThinkSky, DivX, and VSO Software are just a couple examples of instances where you might see an avcodec.dll error. The context of the avcodec.dll error is an important piece of information that will be helpful while solving the problem. How to Fix Avcodec.dll Errors Do not download avcodec.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 avcodec.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 avcodec.dll error. Restore avcodec.dll from the Recycle Bin. The easiest possible cause of a "missing" avcodec.dll file is that you've mistakenly deleted it. If you suspect that you've accidentally deleted avcodec.dll but you've already emptied the Recycle Bin, you may be able to recover avcodec.dll with a free file recovery program. Recovering a deleted copy of avcodec.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 avcodec.dll file. If the avcodec.dll DLL error occurs when you use a particular program, reinstalling the program should replace the file. Try your best to complete this step. Reinstalling the program that provides the avcodec.dll file, if possible, is a likely solution to this DLL error. Run a virus/malware scan of your entire system. Some avcodec.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 avcodec.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 avcodec.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 avcodec.dll. If, for example, you're receiving a "The file avcodec.dll is missing" error when you play a 3D video game, try updating the drivers for your video card. The avcodec.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 avcodec.dll errors began after updating a particular hardware device's driver. Install any available Windows updates. Many service packs and other patches replace or update some of the hundreds of Microsoft distributed DLL files on your computer. The avcodec.dll file is most likely not included in one of those updates, but an update from Microsoft might be required in order for the avcodec.dll file to work properly. Test your memory and then test your hard drive. We've left the majority of hardware troubleshooting to the last step, but your computer's memory and hard drive are easy to test and are the most likely components that might cause avcodec.dll errors as they fail. If the hardware fails any of your tests, replace the memory or replace the hard drive as soon as possible. Repair your installation of Windows. If the individual avcodec.dll file troubleshooting advice above is unsuccessful, performing a startup repair or repair installation should restore all Windows DLL files to their working versions. Again, just like how Windows Update might provide the correct set of files to make avcodec.dll work properly, so too might a repair of Windows. Use a free registry cleaner to repair avcodec.dll related issues in the registry. A free registry cleaner program may be able to help by removing invalid avcodec.dll registry entries that might be causing the DLL error. We rarely recommend the use of registry cleaners. We've included the option here as a "last resort" attempt before the destructive step coming up next. Perform a clean installation of Windows. A clean install of Windows will erase everything from the hard drive and install a fresh copy of Windows. If none of the steps above correct the avcodec.dll error, this should be your next course of action. After installing Windows, reinstall the program that was showing the avcodec.dll error. A fresh installation of both Windows and the third-party software should be enough to fix this DLL error. All the information on your hard drive will be erased during a clean install. Make sure you've made the best attempt possible to fix the avcodec.dll error using a troubleshooting step prior to this one. Troubleshoot for a hardware problem if any avcodec.dll errors persist. After a clean install of Windows, your DLL problem can only be hardware related. Need More Help? If you're not interested in fixing this DLL 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. Some DLL files are really similar in spelling but should be treated differently than when troubleshooting avcodec.dll errors. The mozavcodec.dll file used by the Firefox browser is one example.