I'm trying to create -through PHP code- a CSV file that the user will download as a sample, fill it up (probably with Excel), and then re-upload it in order to upload data.
Problem is that the user may decide to use special characters of Russian, Greek languages, etc. (for example Δ,Γ,θ,з,в,и, etc)
What encoding should I use? Because I've noticed that UTF-8 CSV files are not supported when double-clicked to open direct with Excel. (Shows strange characters instead of actual ones)
In all my tries I cant create a sample file that if I will open it directly in Excel it will read those special characters...
I've also tried to use UTF8 with BOM and when i open it with Notepad++ it always shows it is UTF8 format not UTF8-BOM