What you will see

Multiple symptoms may indicate a firewall is preventing communication.

• Computer Connection Error displays after selecting the Scan Profile on the printer operator panel.
• Computer Connection Error displays when selecting the scan to Computer option on the printer operator panel.
• Or, you are unable to scan when initiating quick-scans from the printer operator panel, or scans from Lexmark Printer Home.
• The problem persists after restarting the computer.
• You receive an error report which contains any given LM... or lex... process. Click here for illustration.
• You receive some other communication failure error message.
   

Before you continue

You should eliminate other communication issues as a possible root cause for the symptoms described above.

First, if one function is failing you should always try another printer/scanner function to test communication.

For example,

Additional Actions

Suggested Remedy

 
It is possible that a scan function is not working because the process utilized by one of the printer functions is blocked. 

Step 1: Identify you firewall application.

Step 2: Identify any blocked processes that begin with LM or LEX.

Step 3: Grant access or create an exception for the process and a Microsoft™ Windows 7 Firewall Example

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1.   Firewall Identification

Identify your firewall application and identify where you can make changes to your firewall protection settings.

IMPORTANT! This is where you will create exceptions for processes that are listed in the next step below.

Here is a list of possible firewall types, listed from the most common to least common found on PC: 

• 3rd party security software applications; i.e., antivirus software and other 3rd party firewall applications
• Operating system firewalls
• Computer hardware BIOS firewalls
• Router hardware firewalls
• VPN firewalls
   

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2.   Identify the Blocked Process

Now that you have identified your firewall application and where you create exceptions for blocked processes, you will want to use the table below to identify whether a blocked process is visible.

Be aware of your printer model's prefix for the lscn.exe and mon.exe processes.

Model-specific prefixes:

• S310 Series<LMADE>
• S410 Series<LMADG>
• S510 Series<LMADH>
• Pro710 Series<LMADI>
• Pro910 Series<LMADJ>
• Pro4000 Series<LMADK>
• Pro5000 Series<LMACT>
• Pro5500 Series<LMADL>

Common prefixes: <LM>, <lex>

For example, LMADLmon.exe contains the prefix <LMADL> which references a Lexmark Pro5500 inkjet printer.

Process <prefix> - lxcq	Function	Possible error/symptom if process blocked
<prefix>lscn.exe Lean Scan	Required for successful Scan Profile communication.  For example, if you press Scan > Scan Profile...	Computer Connection Error is displayed on the printer.
<prefix>mon.exe Device Monitor	This listens for button presses from the device for operator panel-initiated scanning. For example, if you press Scan > Computer...	No response when you press , or a Computer Connection Error displays on the printer.
LMsmc.exe/ lmab1err.exe (All Models) Status Monitor Center Status Messenger in Windows	The Status Monitor Center controls: Supplies alerts Error message logs Problem resolutions in certain situations	Logs and printer notifications will not be displayed.
LMpsu.exe (All Models) Printer Setup Utility	Allows for the configuration of printer fax settings and address book settings. Lexmark Printer Setup Utility or Fax Setup Wizard utilizes this process.	Unable to add/edit contacts or change settings on the printer from either of these utilities.
LMwpss.exe (All Models) Wireless Print Server Setup Utility	Necessary for the successful configuration your wireless printer. Lexmark Wireless Setup Utility requires this process.	Gray Continue button and the inability to configure wireless configuration parameters on the printer.
(All Models) lextwprotocol.dll, lexnetworkds.ds LMabscw.dll LMabmini.dll LMabtwds.ds LMabtwpro.dll LMabtwui.dll LMabdrs.dll LMabdrs64.dll LMzzz_32__bc.dll LMzzz_32serv.dll	These associated local/network TWAIN files require a network TWAIN compliant application to use them...	If the application that uses these files is blocked by a firewall, then these are files are blocked by association.   Also, make sure your scanning software (.exe) is not blocked by a firewall.

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3.   Grant access or create exception in the Firewall Application

You have now identified the blocked process in your firewall application. You will now need to grant permissions in your firewall application to allow these processes to communicate over the network.

Common Network TWAIN file directory locations 

Some firewall applications require that you enter or identify the directory where the filename is located.  

You can perform a search on the filename to identify the file path.

Click here for examples showing how to create firewall exceptions. 

To summarize, grant permission, access, or an exception for all <prefix> file types( .exe, .dll and .ds) listed below to allow full printer-to-computer communication.

• All <LMALMab>, <LMAlex>, <LMALMzzz>
• S310 Series<LMADE>
• S410 Series<LMADG>
• S510 Series<LMADH>
• Pro710 Series<LMADI>
• Pro910 Series<LMADJ>
• Pro4000 Series<LMADK>
• Pro5000 Series<LMACT>
• Pro5500 Series<LMADL>
   

IMPORTANT! You need to know where your firewall software allows you to grant exceptions or permissions.

NOTE: All firewall manufactures use slightly different terminology to reference this permission granting process; e.g., Permit Always, Allow Full Access, Allow, etc.

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Microsoft Windows 7 Example

If you receive a Windows Security Alert, make sure you select Allow access for any LM process: 

How to grant firewall exceptions with Microsoft's Windows Firewall

If you do not allow access for all LM and LEX processes, you may need to follow the procedure similar to this one. 

To open Windows Firewall and allow exceptions in Microsoft™ Windows 7:

NOTE: Click here for more information provided by Microsoft™.

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Related Article

Firewall Preventing Communication or "Communication Failure" Error When Trying to Scan, Print, or Perform a Smart Solution Function (For older printer models)

Still Need Help?

If you need additional assistance, please contact Lexmark Technical Support. NOTE: When calling for support, you will be asked for your machine/model type and serial number (SN).

Please call from near a computer and printer in case the technician on the phone asks you to perform a task involving one or all of these devices.