If you install ‘a codec pack or a combination of codecs’, multiple codecs will be installed on your system at once.
One misconception is that ‘the more codecs you install, the better it is’ and some users install several codec packs on their system.
However, 90% of the codecs in the codec pack are barely used and it is hard to find videos that use such codecs.
In case you have installed many codecs that you do not need,
1) Unverified and unstable codecs cause program error and many other problems
2) All the codecs installed on the system are checked during video play and lowers the speed of the program
3) When removing the codec pack, some stable codecs that are installed on the system might be removed and problems like the inability to play multimedia files might occur. If you need codecs install it one by one to keep your computer simple and stable.
If problem occurs due to the unstable codec installed on the system, from [ Start → Settings → Control Panel → Program Add/Remove ] remove the codec packs on the list.
Please note that unverified programs might not be completely removed even after selecting to remove the program for your system or remove the codecs that are necessary for your system.
(Depending on cases codecs that are installed when installing regular programs might cause problems. In such case remove the suspicious programs one by one and check if the problems persist.)