Anything can be attached to an email—including harmful downloads. Look for some common warning signs to help keep your computer protected. Watch for dangerous document extensions. Some common harmful extensions passed through email attachments are .js, .vbs, .msi, and .reg. Most email services block these files, but check before you download attachments.
Pay close attention to office files. Office file extensions that end with m contain macros and these are potentially dangerous. Although some businesses use macro-enabled documents, be conscious of extensions such as: .docm, .xlsm, and .pptm,
Know the common safe extensions. In general, it is ok to trust .pdf, .pptx, .docx, .xlsx, .jpg, and .png. ;
, Look over the site that you’re downloading from. If the site has been in existence and is backed by a valid organization, chances are it’s trustworthy.


Files that carry viruses are dangerous. The main file types to avoid are files with extensions such as .exe, .scr, .bat, .com, or .pif. Hackers trick people easily with double extension files. For example, if a file ends in .exe.gif or .bat.scr, do not download it! These double extensions are often a virus or torrent.
 If the signature is valid, the file is more likely to be trusted.


The digital signature is a technique used to validate the authenticity and integrity of a message, software, or digital document. It ensures security and assurance of evidence to origin. To see the digital signature, click the publisher link in the security dialog box that Internet Explorer displays when you first download the file. This will tell you if the signature is valid.
 Even if you trust the site, file, and digital signature, use an online service, like VirusTotal, to scan your file.


Right click your file’s link, and select “Copy link address”
Go to VirusTotal.com and select “Submit a URL”
Paste the your link in the text field and click “Submit URL”
Click “View downloaded file analysis”
If nothing was detected, you can assume that the file is safe and fine to use. If something was malicious within the file, the site will warn you.
Be aware of dangerous email attachments.
Download files safely from websites.
Validate the digital signature.
Submit your file to an online validation.
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