get-agentlog error with line 736 in a file

i have problem with get-agentlog in edge server

when i giving command get-agentlog with start and end date its give error like

Get-AgentLog : The log entry on line 736 in file 'C:\Program Files\Microsoft\Exchange Server\V14\TransportRoles\Logs\Ag
entLog\AgentLog20130422-1.LOG' isn't valid.
At line:1 char:13
+ Get-AgentLog <<<<  -StartDate "20/04/2013" -EndDate "30/04/2013" | where {$_.p1fromaddress -like "skpatel@idmc.coop"}
 | select timestamp,p1fromaddress,recipient,action
    + CategoryInfo          : InvalidData: (2013-04-22T05:3...y is disabled.,:String) [Get-AgentLog], LocalizedExcepti
   on
    + FullyQualifiedErrorId : 53BF9A01,Microsoft.Exchange.Management.AgentLog.GetAgentLog

pls help for resolve

SUNIL PATEL SYSTEM ADMINISTRATOR