Problem sending an attachment using dbo.sp_send_dbmail I am trying to send an attachment using dbo.sp_send_dbmail.
I can't do this
I get the error 
Attachment file \VMName\ListTEAM\LCPP_CP.pdf is invalid.

Just some quick things that I have checked.
I have tried various naming conventions.
I have shared the folder that the attachment is in.
I checked the Log On As in the Services MMC on the VM that the SQL database sits on.
The Log On As for SQL SERVER and SQL SERVER AGENT is SQLReportingAdmin@lan.domain.com
I have given this user SQLReportingAdmin@lan.domain.com access to the directory that the file that I want to send as an attachment is in.
I have triple checked the accuracy of the locations.
The user SQLReportingAdmin@lan.domain.com now has read and execute permissions on C$ on the relevant VM.

The file LCPP_CP.pdf is 72 KB.

The file LCPP_CP.pdf is not read only 
The profile is public

I can send an email without an attachment.
The send_request user in dbo.sysmail_mailitems is domain\SQLReportingAgent

My questions are 


Is there a stored procedure that I can use to check the SQL Engine logged on user?
Is it possible that msdb.dbo.sp_send_dbmail is not running under the SQL SERVER  account?  
If so is there a stored procedure that I can use to check what user msdb.dbo.sp_send_dbmail is using 
Is it possible that this isn't a permissions issue?


My code is below but it is really just boilerplate; the commented lines are the various permutations that I have tried.

EXEC msdb.dbo.sp_send_dbmail

@recipients=N'valid@emailaddress.com',

@body= 'Test Email Body', 

@subject = 'Test Email 18:01',

@profile_name = 'Team Meeting Profile'
--@file_attachments ='\\VMName\c$\TEAMLists\TEAM\LCPP_CP.pdf'
--@file_attachments =N'\\VMName\c$\TEAMLists\TEAM\LCPP_CP.pdf'
--@file_attachments ='\\C:\TEAMLists\TEAM\LCPP_CP.pdf'
--@file_attachments =N'\\C:\TEAMLists\TEAM\LCPP_CP.pdf'
--@file_attachments ='C:\TEAMLists\TEAM\LCPP_CP.pdf'
--@file_attachments =N'C:\TEAMLists\TEAM\LCPP_CP.pdf'
--@file_attachments ='\\VMName\TEAMLists\TEAM\LCPP_CP.pdf'
--@file_attachments ='\\VMName\ListTEAM\LCPP_CP.pdf'
You can check the database mail log by going to management -> right-click database mail -> select view database mail log.  Any errors should be in here, for example:


  Message
  The mail could not be sent to the recipients because of the mail server failure. (Sending Mail using Account 1 (2014-05-16T02:21:47). Exception Message: Cannot send mails to mail server. (A recipient must be specified.).
  )


Also, you could fire up SQL Server Profiler to check the user for sp_send_dbmail.  I think it uses the current user account to send the mail, so I would also confirm your windows account has permissions to the file.