Sorry,no target URLs could be imported

Been having this problem since today.

I tried to import urls from site lists but it keeps giving this error 'Sorry,no target URLs could be imported'

Any idea?

How is that file formated? Maybe wrong encoding or not starting with http:// ?

They are simply text files.I have imported them several times and it has never given this type of problem.

can you send me that file for debug purpose?

You mean the text files? There are many.Some are sitelists,others are plain urls.
Should I send them?

yes please.