Error message in Trados Studio 2017: Specified cast is not valid.

 Hello when I try to search terms in a TM termbase the following error messge appears on the Message Window: Specified cast is not valid. How can I solve this problem? Thanks.

Error file content:

<?xml xml version="1.0"?>

<SDLErrorDetails time="2/17/2017 6:50:05 AM"><ErrorMessage>Specified cast is not valid.</ErrorMessage><Exception><Type>System.InvalidCastException, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</Type><HelpLink/><Source>Sdl.LanguagePlatform.ServerBasedTranslationMemory.Contracts</Source><HResult>-2147467262</HResult><StackTrace>

<![CDATA[ at Sdl.LanguagePlatform.ServerBasedTranslationMemory.Contracts.Entities.LanguageDirectionEntity.get_LanguageDirectionIdentity() at Sdl.LanguagePlatform.TranslationMemoryApi.ServerBasedTranslationMemory.GetTranslationUnitCount() at Sdl.TranslationStudio.TranslationMemoryManager.TranslationMemoryProperties.GeneralSettingsPage.ResetToDefaults() at Sdl.TranslationStudio.TranslationMemoryManager.TranslationMemoryProperties.GeneralSettingsPage.GetControl() at Sdl.Desktop.Platform.WinForms.SettingsUIControl.UpdateActiveSettingsPage() at Sdl.Desktop.Platform.WinForms.SettingsUIControl.set_Host(IAbstractSettingsHost value) at Sdl.Desktop.Platform.WinForms.SettingsDialogForm.set_Host(ISettingsDialog value) at Sdl.Desktop.Platform.Implementation.Settings.SettingsDialog.ShowDialog(IWin32Window owner) at Sdl.TranslationStudio.TranslationMemoryManager.AbstractTranslationMemoryManagementObject.ShowPropertiesDialog(Boolean readOnly)]]>

</StackTrace></Exception><Environment><ProductName>SDL Trados Studio</ProductName><ProductVersion>14.0.0.0</ProductVersion><EntryAssemblyFileVersion>14.0.5812.3</EntryAssemblyFileVersion><OperatingSystem>Microsoft Windows 7 Professionnel </OperatingSystem><ServicePack>Service Pack 1</ServicePack><OperatingSystemLanguage>1036</OperatingSystemLanguage><CodePage>1252</CodePage><LoggedOnUser>Sylvain-THINK\Sylvain</LoggedOnUser><DotNetFrameWork>4.0.30319.42000</DotNetFrameWork><ComputerName>SYLVAIN-THINK</ComputerName><ConnectedToNetwork>True</ConnectedToNetwork><PhysicalMemory>2992372 MB</PhysicalMemory></Environment></SDLErrorDetails>