Reset PuTTY to Default Settings

Restore PuTTY to factory defaults and fix configuration issues

Why Restore PuTTY Defaults?

You might want to reset PuTTY to default settings when:

  • Configuration errors: Settings are corrupted or causing connection issues
  • Fresh start: Want to reconfigure from scratch
  • Troubleshooting: Eliminate custom settings as the cause of problems
  • Clean transfer: Remove all traces before handing over a computer
  • Testing: Compare default behavior vs custom configuration
  • Learning: Start fresh to understand what each setting does

⚠️ Important: Resetting PuTTY will delete ALL saved sessions, host keys, and custom settings. Always backup first!

Backing Up Before Reset

Method 1: Registry Export (Windows)

  1. Open Registry Editor:
    • Press Win + R
    • Type regedit and press Enter
    • Click "Yes" if prompted by User Account Control
  2. Navigate to PuTTY Settings:
    • Go to: HKEY_CURRENT_USER\Software\SimonTatham\PuTTY
  3. Export the Configuration:
    • Right-click on "PuTTY" folder
    • Select "Export"
    • Save as: PuTTY-Backup-2025-10-14.reg
    • Choose a safe location (Documents, cloud storage)

To Restore: Double-click the .reg file to import your settings back.

Method 2: Using PuTTY Session Manager

Third-party tools like SuperPuTTY or mTPuTTY often have built-in export/import features:

  • File → Export Sessions
  • Save to XML or JSON format
  • Easier to view and edit than registry files

Reset Methods

Method 1: Delete Registry Keys (Complete Reset)

⚠️ Warning: This permanently deletes all PuTTY configuration. Backup first!

  1. Open Registry Editor:
    • Press Win + R, type regedit
  2. Navigate to PuTTY:
    • HKEY_CURRENT_USER\Software\SimonTatham\PuTTY
  3. Delete PuTTY Folder:
    • Right-click on "PuTTY"
    • Select "Delete"
    • Confirm the deletion
  4. Close Registry Editor
  5. Restart PuTTY:
    • Launch putty.exe
    • It will start with factory default settings
    • New registry entries will be created automatically

Method 2: Reset Individual Sessions

To reset specific sessions without deleting everything:

  1. In PuTTY Configuration:
    • Launch PuTTY
    • Select the session you want to reset
    • Click "Load"
  2. Load Default Settings:
    • Click "Default Settings" in the session list
    • Click "Load"
    • This resets all options to defaults
  3. Reconfigure as Needed:
    • Enter hostname/IP
    • Adjust any specific settings you need
  4. Save:
    • Enter session name
    • Click "Save"

Method 3: Using PowerShell Script

Automate the reset process with PowerShell:

# PowerShell script to reset PuTTY
# Run as Administrator

# Backup first
$backupPath = "$env:USERPROFILE\Documents\PuTTY-Backup-$(Get-Date -Format 'yyyy-MM-dd').reg"
reg export "HKCU\Software\SimonTatham\PuTTY" $backupPath

Write-Host "Backup saved to: $backupPath"

# Delete PuTTY registry keys
Remove-Item -Path "HKCU:\Software\SimonTatham\PuTTY" -Recurse -Force

Write-Host "PuTTY settings have been reset to defaults."
Write-Host "Restart PuTTY to create fresh configuration."

Method 4: Clean Reinstall

  1. Uninstall PuTTY (if installed via installer)
  2. Delete registry keys as shown in Method 1
  3. Delete PuTTY folder (usually C:\Program Files\PuTTY)
  4. Download fresh copy from putty.org
  5. Install or extract to clean directory
  6. Launch with default settings

Reverting Specific Configuration Changes

Reset Window Appearance

If you just want to reset visual settings:

  1. Load "Default Settings"
  2. Go to Window → Appearance
  3. Note default font: typically Courier New, 10-point
  4. Window → Colours: Use default color scheme
  5. Save to your session

Reset SSH Settings

To reset SSH configuration without losing sessions:

  1. Connection → SSH: Use SSH-2 only (default)
  2. Connection → SSH → Auth → Credentials: Remove private key file
  3. Connection → SSH → Tunnels: Remove all port forwards
  4. Connection → Data: Clear auto-login username if you want password prompts

Reset Host Keys

If you're having host key verification issues:

  1. Open Registry Editor
  2. Navigate to:
    • HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\SshHostKeys
  3. Delete Specific Key:
    • Find the entry for your server
    • Right-click and delete
    • Next connection will prompt for new host key
  4. Or Delete All:
    • Delete entire "SshHostKeys" folder
    • All servers will require host key acceptance

Restoring from Backup

From Registry Export

  1. Locate your backup .reg file
  2. Double-click the file
  3. Click "Yes" when prompted
  4. Click "OK" to confirm import
  5. Restart PuTTY to load restored settings

Selective Restore

To restore only specific sessions:

  1. Open the .reg file in a text editor
  2. Find the session you want to restore
  3. Copy that section to a new .reg file
  4. Import the new file

Common Default Settings

SettingDefault Value
Port22 (SSH)
Connection TypeSSH
Terminal Rows24
Terminal Columns80
FontCourier New, 10-point
Scrollback Lines2000
Character SetUTF-8
Close Window on ExitOnly on clean exit
SSH Protocol2 only
Keepalive Seconds0 (disabled)

Troubleshooting Reset Issues

Settings Not Resetting

Possible causes:

  • Registry keys not fully deleted
  • PuTTY still running in background
  • Permissions issue preventing deletion

Solutions:

  1. Close all PuTTY windows completely
  2. Check Task Manager for putty.exe processes
  3. Run Registry Editor as Administrator
  4. Reboot and try again

Can't Access Registry

Solutions:

  • Run regedit as Administrator
  • Check if your account has admin privileges
  • Use portable PuTTY version that doesn't use registry
  • Ask IT department for assistance (corporate environment)

Backup Won't Restore

Possible causes:

  • Corrupted .reg file
  • Different Windows version
  • Different PuTTY version

Solutions:

  1. Open .reg file in text editor to verify contents
  2. Try importing from a different backup
  3. Manually recreate sessions if necessary
  4. Use PuTTY Connection Manager for better backup/restore

Best Practices

  • ✅ Backup regularly, especially before major changes
  • ✅ Name backups with dates for version control
  • ✅ Store backups in cloud storage for access anywhere
  • ✅ Test backups by restoring to a different machine
  • ✅ Document custom settings in session notes
  • ✅ Keep a "clean default" session for reference
  • ✅ Use descriptive session names to avoid confusion
  • ❌ Don't delete registry keys without backing up first
  • ❌ Don't share backup files with private key paths
  • ❌ Don't reset if a simple setting change will fix the issue

Alternative: Portable PuTTY

Consider using portable PuTTY to avoid registry dependencies:

  • No registry entries - settings stored in files
  • Easy to backup (just copy folder)
  • Run from USB drive
  • Multiple instances with different configurations
  • Easier to reset (delete settings file)

Related Resources

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