Why do attachments in emails get blocked?

In order to prevent our users from potential viruses, Feishu Mail does not allow users to upload certain file types including:

File name extension	File type
.app	Executable Application
.bat	Batch Processing
.chm	Compiled HTML Help, may contents JavaScript
.cmd	DOS CP/M Command File, Command File for Windows NT
.com	Command
.cpl	Windows Control Panel Extension (Microsoft)
.csh	csh Script
.dll	Executable Dynamic Library
.exe	Executable File
.hta	HTML executable file format
.jar	Java Archive, Executable
.js	JavaScript Source Code
.jse	JScript Encoded Script File
.ksh	UNIX Shell Script
.lnk	Windows Shortcut File
.msc	Microsoft Management Console Snap-in Control File (Microsoft)
.msh	Microsoft Shell
.msh1	Microsoft Shell
.msh2	Microsoft Shell
.mshxml	Microsoft Shell
.msh1xml	Microsoft Shell
.msh2xml	Microsoft Shell
.msi	Windows Installer File (Microsoft)
.msp	Windows Installer Update
.mst	Windows SDK Setup Transform Script
.msu	Windows Update file
.pif	Windows Program Information File (Microsoft), can be Executed
.pl	Perl script
.prg	Program File
.ps1	Windows PowerShell
.ps1xml	Windows PowerShell
.ps2	Windows PowerShell
.ps2xml	Windows PowerShell
.psc1	Windows PowerShell
.psc2	Windows PowerShell
.psd1	Windows PowerShell
.psdm1	Windows PowerShell
.py	Python script
.pyc	Python script
.pyo	Python script
.pyw	Python script
.pyz	Python script
.pyzw	Python script
.scf	Windows Explorer Command
.scr	Windows Screen Saver, Executables
.sct	Windows Script Component, Foxpro Screen (Microsoft)
.shb	Windows Shortcut into a Document
.shs	Shell Scrap Object File
.vb	VBScript File or Any Visual Basic Source
.vbe	VBScript Encoded Script File
.vbs	VBScript Script File, Visual Basic for Applications Script
.ws	Windows Script File
.wsc	Windows Script Component
.wsf	Windows Script File
.wsh	Windows Script Host Settings File

If Feishu Mail users try to upload such files as attachment, the action will be blocked. If Feishu Mail users receive such files in emails, they'll be warned before they open such files.

What can you do to send such files?

If you need to send a file with one of these extensions to another Feishu user, please upload the file to Docs and add other Feishu user as a collaborator.