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Lexmark MX911

Lexmark MX911

'Optimize Fax Compatibility' Settings Available to Troubleshoot Fax Issues


hat you will see

Line noise, interference, or fax topology leads to a loss in fax-signal strength (attenuation) and negatively influences fax performance. This can lead to inconsistent fax-send and fax-receive transmissions.

When to use

The proceeding remedy should be used only in situations where you are getting persistent fax failures. In the event that these settings work, you can back track and tweak settings to optimize performance as long as consistency is maintained.

Suggested remedy

Enable Fax Compatibility Mode.

To do this:

  1. Type in the IP address of the printer in the a web browser, e.g.,

  2. Click Settings.

  3. Click Fax Settings.

  4. Click Analog Fax Setup.

  5. Click Optimize Fax Compatibility.

  6. Click Change Settings and observe the Submitting selection message.

Settings changed

The following settings are altered or set back to their original default values:

  • Max Send Speed: 9600
  • Max Recv Speed: 9600
  • CallerID: Disabled
  • Line Connected Detection: Disabled
  • Line in Wrong Jack Detection: Disabled
  • Line in Use Detection: Disabled
  • Distinctive Rings: All Rings
  • Fax ID: Fax Number
  • Memory Use: Equal
  • Scan Resolution: Standard
  • Scan Content: Text
  • Behind a PABX: On
  • ECM: On
  • Enable Fax Scans: On
  • Enable Driver Fax: On
  • Enable Color Fax Scan: Off by default
  • Auto Convert Color to Mono: On
  • Enable Fax Receive: On
  • Enable Color Fax Receive: On
  • Holding Faxes: Off
  • Homologation Settings: Default for Country

Still need help?

If you need additional assistance, please close this window, go to your product's support page and locate

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