• Microsoft Expands List of Blocked File Types in Outlook on the Web

    Posted on September 20, 2019 by in News

    Microsoft this week announced plans to add some new file extensions to the list of file types that are blocked in Outlook on the web.

    When the change will be operated, it will immediately result in Outlook on the web users no longer being allowed to download attachments that have those file extensions, the tech giant explains.

    The newly blocked file types, Microsoft claims, are rarely used, which means that the modification will have no impact on most organizations.

    File types affected by the change include ones used by programing languages: “.py”, “.pyc”, “.pyo”, “.pyw”, “.pyz”, “.pyzw” (all used by Python); “.ps1”, “.ps1xml”, “.ps2”, “.ps2xml”, “.psc1”, “.psc2”, “.psd1”, “.psdm1”, “.psd1”, “.psdm1”, “.cdxml” and “.pssc” (all used by PowerShell); and “.jar” and “.jnlp” (both used by Java).

    Moreover, the tech giant will block “.appref-ms” (used by Windows ClickOnce), “.udl” (Microsoft Data Access Components (MDAC)), “.wsb” (Windows sandbox), and “.cer”, “.crt” and “.der” (used by digital certificates).

    Microsoft also decided to block “.appcontent-ms”, “.settingcontent-ms”, “.cnt”, “.hpj”, “.website”, “.webpnp”, “.mcf”, “.printerexport”, “.pl”, “.theme”, “.vbp”, “.xbap”, “.xll”, “.xnk”, “.msu”, “.diagcab” and “.grp”. These are used by various applications and, while associated flaws have been patched, some organizations might still use older versions of the software.