You can use file mask to include only *.html
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Bug reports without an attached log file are usually useless.
I could help if you describe what step you are having problems with.
Yes, you can upload whole folder or set of files using WinSCP at once.
For general help on uploading, please see
I'd like to transfer all the htm files on my local site to my server, including the main dir and all sub dirs. Hopefully this is possible with one command?
Do you want to do that from the GUI or automate it?