By default location for SRM logs are as mentioned below:-

For SRM 4.x and 5.x:

    On Windows XP and Server 2003: %ALLUSERSPROFILE%\Application Data\VMware\VMware vCenter Site Recovery Manager\Logs\
    On Windows Server 2008 and 2012: \ProgramData\VMware\VMware vCenter Site Recovery Manager\Logs\
    On Windows Vista, 7: %ALLUSERSPROFILE%\VMware\VMware vCenter Site Recovery Manager\Logs\

Refer to below VMware KB article for more details.

https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1021802

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Refer to below KB Article to export diagnostic logs for troubleshooting purpose:-

https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1009253