I can transfer file using PSCP:
C:\\>pscp -pw -r -p user@Server:
B
Use the following code:
C:\>pscp -i "path\of\the\privatekey\privatekey.ppk" C:\temp\example_file.txt user@server:/path/file/to/be/stored
Note the quotes for the private key path and the private key should be in .ppk format.
The connection refused error may also be due to the wrong port. In that case, you need to mention the correct port by the following code :
C:\>pscp -i "path\of\the\privatekey\privatekey.ppk" -P 8022 C:\temp\example_file.txt user@server:path/file/to/be/stored
Note that 8022 is the port number and the P is uppercase. Hope this helps.