Visual Studio Assembly C sharp (unavailable)

how can i fix the error ?

&(ampersand ) is in the script somewhere in the file instead of / (slash)

how can i open and edit the script (Xml document )?

THE ERROR:

XmlException: a name did not start with a legal character 32 ( ) Line 58, position 31. Mono.Xml2.XmlTextReader.ReadName (System.String& prefix, System.String& localName) Mono.Xml2.XmlTextReader.ReadName () Mono.Xml2.XmlTextReader.ReadEntityReference (Boolean ignoreEntityReferences) Mono.Xml2.XmlTextReader.ReadReference (Boolean ignoreEntityReferences) Mono.Xml2.XmlTextReader.ReadText (Boolean notWhitespace) Mono.Xml2.XmlTextReader.ReadContent () Mono.Xml2.XmlTextReader.Read () System.Xml.XmlTextReader.Read () Mono.Xml.XmlFilterReader.Read () System.Xml.Linq.XElement.LoadCore (System.Xml.XmlReader r, LoadOptions options) System.Xml.Linq.XNode.ReadFrom (System.Xml.XmlReader r, LoadOptions options) System.Xml.Linq.XContainer.ReadContentFrom (System.Xml.XmlReader reader, LoadOptions options) System.Xml.Linq.XElement.LoadCore (System.Xml.XmlReader r, LoadOptions options) System.Xml.Linq.XNode.ReadFrom (System.Xml.XmlReader r, LoadOptions options) System.Xml.Linq.XContainer.ReadContentFrom (System.Xml.XmlReader reader, LoadOptions options) System.Xml.Linq.XElement.LoadCore (System.Xml.XmlReader r, LoadOptions options) System.Xml.Linq.XNode.ReadFrom (System.Xml.XmlReader r, LoadOptions options) System.Xml.Linq.XContainer.ReadContentFrom (System.Xml.XmlReader reader, LoadOptions options) System.Xml.Linq.XElement.LoadCore (System.Xml.XmlReader r, LoadOptions options) System.Xml.Linq.XNode.ReadFrom (System.Xml.XmlReader r, LoadOptions options) System.Xml.Linq.XContainer.ReadContentFrom (System.Xml.XmlReader reader, LoadOptions options) System.Xml.Linq.XDocument.ReadContent (System.Xml.XmlReader reader, LoadOptions options) System.Xml.Linq.XDocument.LoadCore (System.Xml.XmlReader reader, LoadOptions options) System.Xml.Linq.XDocument.Load (System.IO.TextReader reader, LoadOptions options) System.Xml.Linq.XDocument.Parse (System.String s, LoadOptions options) System.Xml.Linq.XDocument.Parse (System.String s) SyntaxTree.VisualStudio.Unity.Bridge.ProjectFilePostprocessor.OnGeneratedCSProject (System.String path, System.String content) System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:222) Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation. System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:232) System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MethodBase.cs:115) UnityEditor.AssetPostprocessingInternal.CallOnGeneratedCSProject (System.String path, System.String content) (at C:/buildslave/unity/build/Editor/Mono/AssetPostprocessor.cs:178) UnityEditor.VisualStudioIntegration.SolutionSynchronizer.SyncProjectFileIfNotChanged (System.String path, System.String newContents) (at C:/buildslave/unity/build/Editor/Mono/VisualStudioIntegration/SolutionSynchronizer.cs:315) UnityEditor.VisualStudioIntegration.SolutionSynchronizer.SyncProject (MonoIsland island, System.Collections.Generic.Dictionary`2 allAssetsProjectParts, UnityEditor.Scripting.Compilers.ResponseFileData responseFileData, System.Collections.Generic.List`1 allProjectIslands) (at C:/buildslave/unity/build/Editor/Mono/VisualStudioIntegration/SolutionSynchronizer.cs:308) UnityEditor.VisualStudioIntegration.SolutionSynchronizer.GenerateAndWriteSolutionAndProjects (ScriptEditor scriptEditor) (at C:/buildslave/unity/build/Editor/Mono/VisualStudioIntegration/SolutionSynchronizer.cs:240) UnityEditor.VisualStudioIntegration.SolutionSynchronizer.Sync () (at C:/buildslave/unity/build/Editor/Mono/VisualStudioIntegration/SolutionSynchronizer.cs:212) UnityEditor.VisualStudioIntegration.SolutionSynchronizer.SyncIfNeeded (IEnumerable`1 affectedFiles, IEnumerable`1 reimportedFiles) (at C:/buildslave/unity/build/Editor/Mono/VisualStudioIntegration/SolutionSynchronizer.cs:191) UnityEditor.SyncVS.PostprocessSyncProject (System.String[] importedAssets, System.String[] addedAssets, System.String[] deletedAssets, System.String[] movedAssets, System.String[] movedFromAssetPaths) (at C:/buildslave/unity/build/Editor/Mono/SyncProject.cs:175) UnityEditor.AssetPostprocessingInternal.PostprocessAllAssets (System.String[] importedAssets, System.String[] addedAssets, System.String[] deletedAssets, System.String[] movedAssets, System.String[] movedFromPathAssets) (at C:/buildslave/unity/build/Editor/Mono/AssetPostprocessor.cs:134) UnityEditor.Modules.ModuleManager:RegisterAdditionalUnityExtensions()