I can't export images to the hard drive

When I try to export the images from light room CC, to the hard drive, I do it as I have always done but lately, I get a message that says its files cut  not written, last night an LTR technician entered my computer and he try to solve the problem, and I think he did it, but when he left, I tried, and I got the same message his files cut no be written, what do I do? Please