I do not know what is going on,every time i searched for something, i ended up with a lot of files of 851.7ko and
my antivirus tells me that it is a virus.
i would like to know if you have the same problems?

I've come across those types of "files" before but I've never downloaded one before. I knew they were a virus long before I ever saw one in a search.

In fact, it has been more than a year since those files appeared in LimeWire. Lately, it does not matter what program name you type in the search box, there will always be a file with 851.7 kb under that name.
Just about every friend of mine quit using LimeWire for that reason.
I think the authors of LimeWire should create a WARNING "box' above the LimeWire main screen saying something like this: "Do not download any file that has a size of 851.7 kb." and update it as necessary. Most LimeWire users do not come to these forums, so the only way for them to know is a warning message.
It really has gotten to the point where something needs to be done.

I was under the impression they started to show in about February of this year. But they've certainly spread more predominantly .... being spammed across the network.

AFAIK LW is designing a spam filter which will cater for these types of search results. But in the mean time, you can ignore them now you know what they are. As soon as you press the search button, double-click the top of the size column in the results window & this will keep larger files at the top ... thus less chance for confusion. Basically ignore any files less than 2 MB (2,000 KB). See example image Arrange search results by size (click on link)

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