A lot of users were either deleting or renaming the ClientRegistry.blob file in order to refresh Steam files and fix certain issues regarding the starting of the client and the problems with connectivity which occur as soon as the user types in his credentials. This was one of the numerous methods used to fix certain issues related to the Steam client and it was successful for a long time. However, certain users have complained that the file no longer exists in some of their installations, especially regarding those people who only recently installed Steam on one of their computers.
A lot of people have reported that altering the file simply doesn’t solve anything anymore and some people have reported that the file is missing from their Steam directories, leading them to think that the lack of this file is causing their client to malfunction. The file itself was located in the Steam’s directory folder outside of any subfolders. People used to either delete the file or rename it to something else. Then, they would exit Steam and kill all of its processes and reopen Steam again. Steam would then create a new file in the same directory with the same data and that was used to solve around 25% of all Steam-related problems. The file itself is some kind of a binary cache used to store certain settings and preferences.
However, several years ago, Steam users began to notice how the file has become obsolete in the Steam folder and deleting it or removing it would cause no change to the client. Additionally, people who only recently joined Steam didn’t notice the file at all and it’s safe to conclude that Steam is no longer using the file for any purposes.