Originally Posted by HassanMirza
Thanks anyway for your help.
I have another question. Are these released via leaks?
Typically yes. As a very general rule HTC does not release RUUs to the general public for non-developer devices. That being said, there are occasions when HTC will post them. For example HTC has officially posted current RUUs for AT&T & T-Mobile M8s here in the US. Those RUUs were posted at the request of HTC's client, in this case the two carriers mentioned above.
Software versions containing the 401 SKU (like yours) are WWE ROMs (world wide English) and are not specific to one particular carrier or country and therefore almost never have an accompanying RUU publicly released. Any RUU posted online for that SKU is almost certainly a leak, as are the vast majority of RUUs available. Unfortunately at this time the leaks are few and far in between. There have been an Asian RUU leaked & Verizon and Sprint RUUs leaked as well, but nothing for Europe.