# Gmail 552 5.7.0: content presents a potential security issue

URL: https://iblockspam.com/smtp-errors/552-5-7-0
Last updated: 2026-11-03

Code: 552 5.7.0 (permanent failure, the message bounced)
Provider: Gmail / Google Workspace

Gmail blocked the message because something in it, usually an attachment type, a macro document or an encrypted archive, could carry malware. The message wasn't delivered.

What the bounce says:

```
552 5.7.0 This message was blocked because its content presents a potential security issue.
```
Start of Gmail's text for 552 5.7.0, as listed in Google's SMTP errors reference (the published line goes on to point to its blocked file types page).

Google's SMTP reference lists 552 5.7.0 "This message was blocked because its content presents a potential security issue" and links to its page on file types blocked in Gmail. That page explains that Gmail blocks messages that may spread viruses, such as messages that include executable files or certain links.

Google lists what it doesn't allow: certain file types, including in compressed form (like .gz or .bz2) or inside archives (like .zip or .tgz); documents with malicious macros; and password-protected archives with archived content. The blocked types include .exe, .bat, .cmd, .js, .jar, .msi, .ps1, .scr, .vbs, .iso, .img, .lnk and many others, and Google says it updates the list often. A message can also be blocked without any attachment when its content, images or links might share viruses.

Renaming a file to dodge the check isn't a fix and looks like the behavior of malware. If the file is legitimate, Google's suggestion is to share it through Google Drive or another file-sharing link instead.

## Common causes

- An attachment of a blocked type, such as .exe, .js, .iso or .lnk, including inside a .zip.
- A password-protected archive that Gmail can't scan.
- An Office document with macros that Gmail considers malicious.
- Links or content in the message that Gmail associates with malware.

## How to fix it (sender)

- Share the file through Google Drive or another file-sharing link instead of attaching it.
- Don't zip, encrypt or rename executables to get past the check.
- If you didn't send an attachment, check the links in your message and your signature, and scan your computer.

## How to fix it (recipient or admin)

- Ask the sender to share the file through a link; Gmail doesn't let users receive blocked file types as attachments.

**Q: How do I send an .exe or a script file to a Gmail user?**
Upload it to Google Drive or another file-sharing service and send the link. Gmail blocks those file types as attachments, even inside a zip, and Google suggests sharing through Drive instead.

**Q: Why was my message blocked as a security issue with no attachment?**
Google says messages can be blocked without attachments when the content, images or links might share viruses. Check every link, including in your signature, and remove any that point to file downloads you don't control.

Sources:
- Gmail SMTP errors and codes (Google Workspace Admin Help): https://knowledge.workspace.google.com/admin/support/troubleshooting/gmail-smtp-errors-and-codes
- File types blocked in Gmail (Gmail Help): https://support.google.com/mail/answer/6590
- RFC 3463: Enhanced Mail System Status Codes: https://www.rfc-editor.org/rfc/rfc3463

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