See the link below for a file named "sychost.exe".. If the spelling includes a "Y", then it's probably malware and you need to run scans and remove such:

If it appears to be malware, then download, install, update, and run a second tool as well.. Here's the link:

Malwarebytes Antimalware

On the other hand, if the spelling is "svchost.exe" (there's a letter "V" in this one), then the file is probably a legitimate "generic host process" file used for a number of processes including internet connections and should be allowed.. Frequently, there will be a number of "svchost.exe" attempting to access the net because of various services running on your computer. That's usually normal and they should be allowed.

Research EXACTLY where the file is originating from (which directory, etc.), then allow it if all seems correct.

Hope this helps.