This question may be too common and the information I have may be too sparse, but I am out of ideas on what the problem may be.
One week ago, WinSCP did just fine with the exact same task of uploading a file to the server in question. I am not aware of any changes made to either the server or my PC that could cause the issue. I do not recall, if there was an automatic Windows update during that week though.
The problem: I cannot send files to my server, neither via FTP nor via SCP using WinSCP.
I tried the same task using FTP with TotalCommander and using SCP via Putty's PSCP. Both worked like charm. No special settings needed.
When using WinSCP whatever protocol, I run into a timeout (Host is not communicating for 15 seconds). I checked the server logs but found no information on a transfer failure.
WinSCP 5.7 (5125)
Windows 7 Home Premium 64-bit SP1
SCP and FTP protocol via GUI (Commander)
Any helpful information and hints on the cause or where to check for more information are most welcome.