DSY Weather File Issues

[sduffy]

Hello,

I am having a bit of trouble in finding a CIBSE weather file that I have recently downloaded and wondered if anyone may be able to help.

It is an old Manchester_Ringway.dsy weather file which I have saved in the folder location C:\Program Files (x86)\IES\Shared Content\Weather as I have with previous weather files.

However, when i use Aplocate within ApacheSim it is unable to find it? Does the extension need to be as an .epw or .fwt file?

Can you also confirm what the .epw .twd,.fwt file formats mean and when they should be used?

Thank you in advance.
Regards,