> Source: [sk106064](https://support.checkpoint.com/results/sk/sk106064)

# sk106064 - Unable to login to Gaia OS with TACACS+ username that contains a "\" character

| Property | Value |
|----------|-------|
| Solution ID | sk106064 |
| Date Created | 2015-05-14 |
| Last Modified | 2015-05-18 |
| Technical Level | Advanced |
| Products | Security Gateway, Security Management Server, Multi-Domain Security Management Server |
| Versions | R82.10, R82, R81.20, R82.10, R82, R81.20, R82.10, R82.20, R81.20, R82, R82.20 |
| OS | Gaia |

## Symptoms

- * The authentication request on Gaia OS fails when authentication to a joined domain with TACACS+ username that contains a "\\" character.

* */var/log/messages* file shows the following:

  ```
  
  sshd[PID]: Accepted password for DOMAIN\\USERNAME from X.X.X.X port XXX ssh2
  sshd[PID]: pam_unix(sshd:session): session opened for user DOMAIN\USERNAME by (uid=0)
  cp_tacp_helper_1: Failure to process credentials for RADIUS/TACACS user 'DOMAIN\USERNAME': can't allow ':' or '\' in a user name
  PAM-tacplus[PID]: Not setting non local user info for 'DOMAIN\USERNAME': difficulty from helper /usr/libexec/cp_tacp_helper_1
  clish[PID]: user logged from DOMAIN\USERNAME
  clish[PID]: User DOMAIN\USERNAME logged out due to an error from CLI shell
  cp_tacp_helper_1: Failure to process credentials for RADIUS/TACACS user 'DOMAIN\USERNAME': can't allow ':' or '\' in a user name
  PAM-tacplus[PID]: Not setting non local user info for 'DOMAIN\USERNAME': difficulty from helper /usr/libexec/cp_tacp_helper_1
  sshd[PID]: pam_unix(sshd:session): session closed for user DOMAIN\USERNAME
  ```

## Cause

Currently, the "\\" character is not supported.

## Solution

This solution requires authentication. Please log in to view the full solution.

---

# Agent Instructions

This content is from the Check Point Support Center (https://support.checkpoint.com), the official knowledge base for Check Point cybersecurity products.

## Navigating This Knowledge Base

- **Complete index**: [llms.txt](https://support.checkpoint.com/llms.txt)
- **All SK articles**: [SecureKnowledge Sitemap](https://support.checkpoint.com/sitemaps/secureknowledge-sitemap-index.xml)
- **SK article URL pattern**: `https://support.checkpoint.com/results/sk/{skId}`
- **Markdown responses**: AI bot User-Agents automatically receive `text/markdown` content