Microsoft Defender has previously experienced a malfunction, which may skip certain files when performing virus scans. There may be a security risk.
At that time, Microsoft confirmed the problem and released a new definition update to fix the problem, but it was not long before Microsoft Defender again had a similar problem.
According to bleepingcomputer reports, the definition update previously pushed by Microsoft seems to have some errors. This error will cause the anti-virus service to crash directly when scanning files.
After a discussion on the Reddit forum, users found that the problem was caused by the file name of some files. When the file name contains two dots, Microsoft Defender will start to crash.
According to user feedback, this problem will be encountered when using Microsoft Defender to perform a quick scan. When the crash is encountered, the scanning process will be automatically terminated. At the same time, the system will also pop up a notification that the user needs to manually restart the Microsoft Defender service.
After the preliminary investigation, the problem is a bug caused by the definition update previously released by Microsoft. Since the definition update is automatically installed, many users are affected.
After receiving user feedback, Microsoft has quickly released a new definition update to fix the problem. If users encounter this error, please check the update to ensure that the new version has been upgraded.
After installing the latest definition update, you can see the version is 1.313.1687.0 in Microsoft Defender About, this version is the latest repair version.
This problem occurs in v1.313.1638.0 and v1.313.1666.0, so it seems that this is a bug brought by the definition update that Microsoft pushed a few days ago.