I am using SmarterMail 15 in a windows system 2012 server with 2000+ users. Recently i am facing mail delivery problem and the spool messages increases immediately. when i checked the delivery log i found the error File not found. I am using cyren antivirus and also  avast antivirus for file system. I have also excluded the spool path from avast scanning. What would be the reason for this File not found error. Can anyone suggest a solution?

 

[2018.02.06]    at System.IO.File.InternalDelete(String path, Boolean checkHost)
[2018.02.06] 10:30:05 [19608] Error adding message to spool stat tracker: Could not find file 'D:\Spool\SubSpool3\22319608.eml'.
[2018.02.06]    at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
[2018.02.06]    at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share)
[2018.02.06] 10:30:05 [19608] Exception: Could not find file 'D:\Spool\SubSpool3\22319608.eml'.
[2018.02.06]    at System.IO.FileInfo.get_Length()
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