My PM's and replys to threads not getting thru

I have always used my home computer and my office computer to hobby and after I had a company come on remotely on both and clean out some unwanted stuff to speed it up I now find that on both I cannot respond to a PM or send a PM nor can I reply to a tread when I want to. I am having to use a backup computer to send you this. Any suggestions as to what they may have deleted so I can get those two computers back way they should be. Much thanks.