SFC Scannow - what is this team?

There have been errors in the Windows operating system since its inception. They occurred in almost all versions. It looks different. An error message pops up, a "blue screen of death" is displayed, the application crashes or the system reboots altogether. In most cases, this is due to a violation of the integrity of the system and files important for the operation. But the reasons for such consequences can serve as a virus attack, and the general system instability and failures.

Beginning with Windows 2000, a mechanism was implemented inside it that allows to check the integrity of important files with the possibility of their recovery. The name of the utility is SFC. The most well known method of application is SFC / scannow. What this team is and what it is used for will be discussed in detail in this article.

SFC / scannow - what is it?

In general, on the Internet, this bundle is used throughout the instructions and the like. In fact, the expression following the slash is just a key or argument to the SFC utility.

SFC is a special program designed to check the status of system files, in order to find distortions, violations of integrity or even their absence. You need to run it with certain arguments, the list of which will be presented below.

• SFC /? This key will list all available arguments with examples of their use. Actually, the same effect can be achieved when calling simply SFC without attachments;
• SFC / scannow. What is this key? It performs a scan, calculates whether the system files have been modified and, if found, starts the recovery. The whole cycle will happen in default mode, i.e. User intervention after the introduction of the command is not required. Sometimes the output of this procedure can display something like "SFC / scannow can not recover some files". This means that the file is corrupted so that it can not be restored or is completely missing;

• / Verifyonly. This argument simply checks files, without restoring them;
• / Scanfile = The path to the file to be scanned. Scan and attempt to restore one specific file;
• / Verifyfile = The path to the file to be scanned. Similar to the previous command, only does not restore found problem instances;

Additional commands

• / Offwindir = the drive letter on which to scan. Allows you to check integrity by specifying specifically where the Windows system is installed;
• / Offbootdir = the drive letter from which you want to restore the files. This key is used in conjunction with scannow and the previous argument;
• / Scanonce. This key sets the scheduled check for the next system restart;
• / Scanboot. This argument, like the previous one, plans to scan, only now every time you reboot;
• / Revert. This key cancels the changes applied during the execution of previous commands;
• / Purgecahe. The argument removes the source files from the special cache, which is used for recovery. At the same time, it is checked and filled with current ones, if their integrity is not violated;
• / Cachesize = i. This key sets the size of the cache as desired by the user. The value of i in megabytes is measured.

Examples of using SFC / scannow. What this gives and the output of the results

Use SFC on the command line. This will require administrator rights. To do this, you need to click the "Start" button and go to "Standard". There is a "command line". You need to right-click on it and select "Run as administrator".

A black screen will appear in which the commands will be input and the corresponding result will be displayed. It looks like this:

It can enter one of the above commands, depending on the situation. For example, the first one you can use is SFC / scannow. What will it give? First, the utility will check all the important system files, then compare them with the database from the cache.

If any discrepancies are found, they will be restored. During the operation of the utility, progress is displayed, after which 100% of the result of the procedure will be displayed. There can be several:

• The program did not detect integrity violations. The conclusion of this sentence is that everything is in order with the system;
• A system restart is required to complete the system recovery . Restart Windows and run sfc again. The occurrence of this result when using SFC / scannow recovery may be due to a limited environment. The system proposed a solution.

This list of system responses occurs most often.

Other messages used less often

• The program detected corrupted files, but can not recover some of them. This is not the most favorable option, since the cache storing entire and correct versions of the file may be corrupted;

• The utility can not perform the requested operation. This result is displayed if there is any restriction on the part of the system. It's worth trying to reboot into safe mode and enter commands here;

• The utility detected corrupted files and successfully restored them. This message indicates that all system problems have been fixed. The result of running SFC / scannow in Windows 7 is saved to the Path to the Windows \ Logs \ CBS \ CBS.log folder;

Conclusions and recommendations

Using SFC / scannow in Windows 7, 8, 10 can sometimes lead to unusual results. In the case when the utility says that it has not found any errors, and the system still works unstably, you need to restart SFC again. There are cases when a successful elimination of the problem was realized with a third or even fifth attempt. The same goes for other unsuccessful results. It is also worthwhile to use the presented utility in a safe mode, as certain services and processes will not interfere.

Conclusion

The article discussed in detail the use of the SFC.exe / scannow utility. What it is and how to apply was described in the examples of different keys. To avoid using the SFC utility, it is best to still monitor the system and prevent its destruction and malfunctions. This can be done with antivirus software, scanning and registry cleaning systems. Also, you should carefully monitor what is installed on your computer. And most importantly - to avoid downloading incomprehensible files and programs from suspicious or unfamiliar resources. Observance of the elementary norms of computer literacy will relieve of necessity to use means of check of integrity of system and a call of the master.