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What is the .CAT File Extension?

.CAT File Extension Description:

CAT files, or Catalog files, have the file extension .cat. These files are considered as one of Microsoft's security measures. Microsoft distributes CAT files within updates and drivers to ensure file and data protection.

Catalog files are used to determine that a given set of files within the operating system belong to the same logical group. It basically catalogs files within their rightful place.

Files in the .cat format are made up of multiple data that store in file and page hashes, to determine and ensure the validity of the system and non-Microsoft files. Hashes of a Microsoft driver and the information relevant to it are stored in a .cat file. Each .cat file has a digital signature that is used for validating the integrity of the stored content.

Files with the .cat extension are called when users download application components from the Internet, to avoid multiple instances of trust dialog boxes. Trust dialog boxes are security warnings that inform users before any software installation. The trust dialog box identifies the software component distributor and verifies the publisher's authenticity.

CAT files are supported by a service called Internet Component Download, which is provided by Internet Explorer 5 and its higher versions. This service allows the 'popping out' of the trust dialog box for the operating system's security.

Catalog (.cat) files have other benefits aside from PC protection. One is that it makes Internet software installations simpler and less confusing for users. Since trust dialog boxes are controlled, it only has to appear once. This, then, lessens the number of keystrokes necessary for software downloading.

When a digital signature of a CAT file is corrupted, the entire page and the file hashes within are considered invalid. All versions of Windows operating system updates are digitally signed and are cross-validated against a security catalog (.cat) file.

Author: Microsoft Corporation
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Do you have errors with .CAT files?

The Typical Cause of .CAT files Errors to Occur:

When you get errors with .CAT files you are potential having a critical Windows registry error - this error might be the outcome of damage in your registry and you should move to repair it right away to prevent additional damage to your registry. As long as the errors remain your PC remains capable of potential blue screen errors, system failure and fatal crashes.

Symptoms of .CAT files Errors:

.CAT files errors produce numerous symptoms, including: personal computer locks on start up or shut down, programs lock up, decreased computer speed, built-in speaker beeps, trouble saving files, sluggish behaviour and application installation trouble.

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How to Fix .CAT File Extension Errors    |    Repair .CAT File Errors    |    What is the .CAT File Extension?