Another operation is pending

Question

Hi, i'm using the FTP rebex connection on mobile equipment, but randomically i'm facing with this exception, i don't know why, everything is working good on my FTP and the log is quite clean, here there is the rebex stack trace:

Rebex.Net.FtpExceptionAnother operation is pending.
Raw
Rebex.Net.Ftp.DK()
Rebex.Net.Ftp.EK()
Rebex.Net.Ftp.HN(string A, DG B)
Rebex.Net.Ftp.JO(string A, bool B)
Rebex.Net.Ftp.ChangeDirectory(string remotePath)
Rebex.Net.JI.YB(YF A, bool B)
Rebex.AG.DE(YF A)
Rebex.AG.BE()
Rebex.AG.AE(TransferAction A, WF B, string C, TransferMethod D, MoveMode E, LinkProcessingMode H, ActionOnExistingFiles I, XF J)
Rebex.Net.JI.WE(VF A, LinkProcessingMode B)
Rebex.Net.Ftp.NN(II A)
Inner trace
Properties & Custom Values
FtpStatus   
Pending
Status  
OperationFailure
Status  
OperationFailure
HResult 
-2146233088
TargetSite  
DK

Answer 1

Hi, this exception is thrown when a method of Ftp object instance is called while another method called on the same instance is still running. This is due to a limitation of the FTP protocol which can't perform multiple operations simultaneously on a single session. This means that - for eaxmple - if you need to be able to browse the directory tree while a transfer is in progress, you have to use two FTP sessions (which means two instanced of Ftp object).