Error 0x80040352 dynamics

Hi,

I have a big problem. I try to import all the contacts of my company and i used the Dynamics Template, but when i import them, i have this error "0x80040352"... Dynamics don't want to import contacts who are in the same company, only one because it detected the duplicates.. I think it's a problem with the mapping but i don't know how what to do... Can you help me it's really important

Best regards