please help with this error

Blocking call cancelled


i don tknwo what to do i need to upload some files to my website

UPDATE:
ok, this is what i found out about the problem.

i was having the problem with my laptop which was connected to my at&t dsl service. the weird thing it was working fine yesterday. but today it stopped working.

so i turned on my desktop computer and tried from there using the same software client WSFTP-PRO and could not, still got the same error.

so now what i did, i got my cellphone and shared my internet connection from my mobile to my laptop. and i was able to connect to my site ok. so this means the isp is doing something to black port 21 maybe.