Import unitypackages problem

First, sorry for my English I'm new to unity I import two unity packages, both are character model, they work fine at first but after I restart the unity, some errors occurred

 Scripts named 'sharedassets0.asset' exist in multiple locations (Assets/DO/sharedassets0.asset). Please rename one of the scripts to a unique name.
 Scripts named 'sharedassets0.asset' exist in multiple locations (Assets/Gs/sharedassets0.asset). Please rename one of the scripts to a unique name.
 Scripts named 'sharedassets0.asset' exist in multiple locations (Assets/DO/sharedassets0.asset). Please rename one of the scripts to a unique name.
 Scripts named 'sharedassets0.asset' exist in multiple locations (Assets/Gs/sharedassets0.asset). Please rename one of the scripts to a unique name.

Then I rename one of them and restart the unity. Other errors occurred

 ApplicationException: Unable to find a suitable compiler
 UnityEditor.Scripting.ScriptCompilers.CreateCompil erInstance (MonoIsland island) (at C:/BuildAgent/work/14194e8ce88cdf47/Editor/Mono/Scripting/ScriptCompilers.cs:87)

 Failed to create compiler instance
 Compilation failed because the compiler couldn't be executed!

How can I solve these problem? Thanks