У нас здесь та же проблема - отображается следующая ошибка:
<entry>
<record>334</record>
<time>2019/02/25 12:48:44.893</time>
<type>Error</type>
<source>VisualStudio</source>
<description>SetSite failed for package [Vsix]Source: 'QtVsTools' Description: Could not load file or assembly 'Microsoft.VisualStudio.Threading, Version=15.8.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.VisualStudio.Threading, Version=15.8.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
File name: 'Microsoft.VisualStudio.Threading, Version=15.8.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
 at QtVsTools.Vsix.InitializeAsync(CancellationToken cancellationToken, IProgress`1 progress)
 at Microsoft.VisualStudio.Shell.AsyncPackage.<>c__DisplayClass16_0.<<Microsoft-VisualStudio-Shell-Interop-IAsyncLoadablePackageInitialize-Initialize>b__1>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
 at Microsoft.VisualStudio.Services.VsTask.RethrowException(AggregateException e)
 at Microsoft.VisualStudio.Services.VsTask.InternalGetResult(Boolean ignoreUIThreadCheck)
 at Microsoft.VisualStudio.Services.VsTask.GetResult()

WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.
To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].
</description>
<guid>{15021976-647E-4876-9040-2507AFDE45D2}</guid>
<hr>80070002</hr>
<errorinfo></errorinfo>
</entry>
Наша версия Visual Studio: Microsoft Visual Studio Enterprise 2017 Версия 15.5.1
Мы не можем выполнить обновление до новейшего обновленияиз-за политики компании.