To provide fast search, windows will index the specified files, so in your case since it was 25% i thought it may be windows was indexing a fresh bunch of files. Sorry i am not very sure whats causing this wait for others, but you can try disabling windows search and then again enable it
Its not create problem in all pc but sometime due to hardware,file types or some unknown reason it can slow down (Generally its eat resource in all pc)
Its not create problem in all pc but sometime due to hardware,file types or some unknown reason it can slow down (Generally its eat resource in all pc)