See this MSDN Forum Post for detail on this issue. On a recent project we attempted to use the Microsoft SFTP adapter with GlobalScape EFT Server v7. We found any files over 40KB couldn’t be received. Sending was fine. When attempting the receive files greater than 40KB no errors would be logged on the BizTalk Server, the files just sit there apparently being ignored in the FTP folder. All other smaller files are received successfully from the same folder.
Looking at the server logs we noticed a 552 error which indicates there is not enough resources on the client(BizTalk Server) even though resource usage was low. We tried running the receive handler as 32bit and 64bit with no change.
Working for a consultancy I put a call out to the team and sure enough another customer was having the exact same issue on their project. However, they had both EFT Server v6 and v7. V6 the Microsoft SFTP adapter works fine.
Our solution, revert to the BLogical SFTP adapter. Another customer is using the nSoftware SFTP adapter without fault. Note EFT Server isn’t in the list of servers supported by the adapter, so I guess this can’t be considered a bug as such.