Microsoft Exchange Transport service cannot be started referencing 'Invalid agent assembly path.' error, when some or all of MailEssentials transport agents are enabled

Versions / Builds Affected

2014 R2

Status

Resolved

Problem Summary

Microsoft Exchange Transport service cannot be started when some or all of MailEssentials transport agents are enabled. GfiAvRoutingAgent, GfiAsRtSubmittedAgent and GfiAsRtRoutedAgent must be disabled in order for the Transport service to start.

TT / JIRAID

2061

How to Identify

Microsoft Exchange Transport service cannot be started when some or all of GFI MailEssentials transport agents are enabled. In the Windows EventViewer you see errors similar to: Microsoft Exchange couldn't start transport agents. The Microsoft Exchange Transport service will be stopped. Exception details: Failed to create type 'MEC.ExchangeAgents.GfiAvSmtpAgentFactory' from assembly 'D:\Program Files\GFI\MailEssentials\EmailSecurity\MEC.ExchangeAgents.GfiAvSmtpAgent.dll' due to error 'Invalid agent assembly path.'. : Microsoft.Exchange.Data.ExchangeConfigurationException: Failed to create type 'MEC.ExchangeAgents.GfiAvSmtpAgentFactory' from assembly 'D:\Program Files\GFI\MailEssentials\EmailSecurity\MEC.ExchangeAgents.GfiAvSmtpAgent.dll' due to error 'Invalid agent assembly path.'. ---> System.ArgumentException: Invalid agent assembly path. Checking the Properties->Security of files like ..\GFI\EmailSecurity\Data\rclientsettings.xml, the Network Service has not full permissions or is not present in the list.

Workaround / Fix Details

1. Navigate to the installation folder of GFI MailEssentials 2. Right click on the MailEssentials folder, select Properties then Security and make sure Network Service has full control permissions on the folder. If not, add it or amend as necessary and hit Apply. 3. Click on Advanced and select Change Permissions... then tick the "Replace all child object permissions with inheritable permissions from this object" option and click OK. 4. Verify if files from the Data folder have have the Network Service with full control permissions added. Sometimes even if the Network Service is added with full control permissions to the installation folder of GFI MailEssentials, some files do not inherit these settings, probably due to some environmental factors.

Required Actions

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