7-Zip is a great tool for file archiving. It is a free and open-source application and supports Windows, Mac and Linux operating systems. But when you install 7-Zip on called CRC SHA is added to the right click menu of Windows. But what is this CRC SHA? Is it necessary for a normal user? How to remove it from appearing in the Windows right click menu? We will try to answer all these questions in this article.
What is CRC?
CRC is short for Cyclic Redundancy Check. It is a technique used in computer networks to detect and correct errors in digital data. As most of the modern communication is digital in nature i.e., sequence of 1’s and 0’s, there is a chance that a 1 is replaced by 0 and a 0 is replaced by 1.
Cyclic Redundancy Check or CRC helps in detecting the errors in sequence of bits. It is a popular method of error detection as the algorithm for CRC can be embedded into the hardware (in the firmware to be specific) with just a few lines of code.
What is SHA?
SHA is short for Secure Hash Algorithm. It was designed by the NSA and published by National Institute of Standards and Technology. SHA is a family of cryptographic hash functions that maps a data (or the message) of variable length into a message digest (or hash) of a fixed length.
There are different types of SHA such as SHA-0, SHA-1, SHA-2 and SHA-3. All these hash functions are often used in information security applications such as digital signatures, message authentication codes etc.
SHA in Windows system checks for the files that are downloaded from the internet for any corruption.
What is CRC SHA?
From the previous context, we understood that CRC is used for detecting errors in the information received while SHA authenticates the data with hash values. The combination of CRC and SHA can be used to check the integrity of the data that you downloaded from the internet.
For example, consider you are trying to upgrade the firmware of your router and downloaded the firmware file from the manufacturer’s website. Along with the firmware file, the manufacturer also provides you with a has file.
Now after downloading the firmware, you can use the CRC SHA tool from the 7-Zip sub context menu to generate a has code for the downloaded file. Finally, you can compare both the has files and they are same, then the downloaded file is not modified. But if the has codes are different, then it means that the downloaded file is modified (even very small changes will generate a different has code).
From this example, it is clear that CRC SHA can be very useful in authenticating the files downloaded from internet. So, if you want to send any confidential files over the internet, then you should definitely generate the has code and send it along with the file.
Is CRC SHA Safe?
Many users who installed 7-Zip doesn’t know about CRC SHA and think it as a malware or wonder why is it appearing in the right click menu of Windows. We assure you that CRC SHA is absolutely safe and if you are concerned about the integrity of the files you downloaded from the internet, then we suggest you to keep the CRC SHA tool as it is so that you can easily generate hash codes for the files.
How to remove CRC SHA from Windows?
The latest version of 7-zip makes it easier to generate has values by placing a short cut in the right click sub context menu in Windows. There are some Windows users who are not interested in CRC SHA functionality and want to remove / hide the menu. If you are one of them, then follow along to see how to remove CRC SHA sub context menu from Windows.
Following are the steps to remove CRC SHA from Windows right click menu.
- Open 7-Zip File Manager app (either by clicking on a short cut or searching for it in the start menu).
- Once it is open, select “Options…” tab in the Tools menu.
- The Options window pops up.
- In the 7-Zip tab, uncheck the CRC SHA option at the bottom.
- This will remove CRC SHA option from appearing in the right click menu of Windows.
Conclusion
CRC and SHA are two important tools in computer networking for error detecting and checking file integrity respectively. 7-Zip File Archiver application has integrated the CRC SHA tool so that you can easily check for the authentication of the file that you downloaded from internet.
This article explains the importance of CRC-SHA tool and how you can use this tool to generate hash data for files. But if you are not interested in using this feature and want to remove the CRC-SHA option from appearing in the right click menu of Windows, then we also included the steps to disable that.
