BUG: When running FlowLauncher using ALT+SPACE seeing = Exception: System.IO.FileNotFoundException: Unable to find the specified file.

[slickmrick]

Checks

• I have checked that this issue has not already been reported.

• I am using the latest version of Flow Launcher.

• I am using the prerelease version of Flow Launcher.

Problem Description

I launch FlowLauncher using the hotkeys but immediately get an Exception error. The only thing I can do from here is close FlowLauncher. Incidentally, clicking the URL that it shows me to report the bug does not open my default web browser when I click the link.

To Reproduce

1. ...Turn on PC & login
2. ...FlowLauncher icon is on the task bar
3. ...Press ALT+SPACE to open search box - Error appears with no search box

Screenshots

No response

Flow Launcher Version

2.0.1

Windows Build Number

Microsoft Windows [Version 10.0.17763.805] - Win10 Enterprise LTSC

Error Log

2025-10-04.txt

System.IO.FileNotFoundException: Unable to find the specified file.
Source: DirectWriteForwarder
TargetAssembly: DirectWriteForwarder, Version=9.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
TargetModule: DirectWriteForwarder.dll
TargetSite: Void ConvertHresultToException(Int32)
at MS.Internal.Text.TextInterface.Native.Util.ConvertHresultToException(Int32 hr)
at MS.Internal.Text.TextInterface.Font.AddFontFaceToCache()
at MS.Internal.Text.TextInterface.Font.GetFontFace()
at MS.Internal.FontCache.FontFaceLayoutInfo.IntMap.TryGetValues(UInt32* pKeys, UInt32 characterCount, UInt16* pIndices)
at System.Windows.Media.GlyphTypeface.GetGlyphMetricsOptimized(CharacterBufferRange characters, Double emSize, Single pixelsPerDip, UInt16[] glyphIndices, GlyphMetrics[] glyphMetrics, TextFormattingMode textFormattingMode, Boolean isSideways)
at System.Windows.Media.Typeface.CheckFastPathNominalGlyphs(CharacterBufferRange charBufferRange, Double emSize, Single pixelsPerDip, Double scalingFactor, Double widthMax, Boolean keepAWord, Boolean numberSubstitution, CultureInfo cultureInfo, TextFormattingMode textFormattingMode, Boolean isSideways, Boolean breakOnTabs, Int32& stringLengthFit)
at MS.Internal.TextFormatting.SimpleRun.CreateSimpleTextRun(CharacterBufferRange charBufferRange, TextRun textRun, TextFormatterImp formatter, Int32 widthLeft, Boolean emergencyWrap, Boolean breakOnTabs, Double pixelsPerDip)
at MS.Internal.TextFormatting.SimpleRun.Create(FormatSettings settings, CharacterBufferRange charString, TextRun textRun, Int32 cp, Int32 cpFirst, Int32 runLength, Int32 widthLeft, Int32 idealRunOffsetUnRounded, Double pixelsPerDip)
at MS.Internal.TextFormatting.SimpleTextLine.Create(FormatSettings settings, Int32 cpFirst, Int32 paragraphWidth, Double pixelsPerDip)
at MS.Internal.TextFormatting.TextFormatterImp.FormatLine(TextSource textSource, Int32 firstCharIndex, Double paragraphWidth, TextParagraphProperties paragraphProperties, TextLineBreak previousLineBreak, TextRunCache textRunCache)
at System.Windows.Controls.TextBoxLine.Format(Int32 dcp, Double formatWidth, Double paragraphWidth, LineProperties lineProperties, TextRunCache textRunCache, TextFormatter formatter)
at System.Windows.Controls.TextBoxView.GetFormattedLine(Int32 lineIndex, LineProperties& lineProperties)
at System.Windows.Controls.TextBoxView.System.Windows.Documents.ITextView.GetRectangleFromTextPosition(ITextPointer position)
at System.Windows.Documents.TextSelection.CalculateCaretRectangle(ITextSelection currentTextSelection, ITextPointer caretPosition)
at System.Windows.Documents.TextSelection.UpdateCaretStateWorker(Object o)
at System.Windows.Documents.TextSelection.UpdateCaretState(CaretScrollMethod caretScrollMethod)
at System.Windows.Documents.TextSelection.EnsureCaret(Boolean isBlinkEnabled, Boolean isSelectionActive, CaretScrollMethod scrollMethod)
at System.Windows.Documents.TextSelection.System.Windows.Documents.ITextSelection.UpdateCaretAndHighlight()
at System.Windows.RoutedEventArgs.InvokeHandler(Delegate handler, Object target)
at System.Windows.EventRoute.InvokeHandlersImpl(Object source, RoutedEventArgs args, Boolean reRaised)
at System.Windows.UIElement.RaiseEventImpl(DependencyObject sender, RoutedEventArgs args)
at System.Windows.UIElement.RaiseTrustedEvent(RoutedEventArgs args)
at System.Windows.Input.InputManager.ProcessStagingArea()
at System.Windows.Input.InputManager.ProcessInput(InputEventArgs input)
at System.Windows.Input.KeyboardDevice.ChangeFocus(DependencyObject focus, Int32 timestamp)
at System.Windows.Input.KeyboardDevice.Focus(DependencyObject focus, Boolean askOld, Boolean askNew, Boolean forceToNullIfFailed)
at System.Windows.Input.KeyboardDevice.Focus(IInputElement element)
at System.Windows.Interop.HwndKeyboardInputProvider.OnSetFocus(IntPtr hwnd)
at System.Windows.Interop.HwndKeyboardInputProvider.FilterMessage(IntPtr hwnd, WindowMessage message, IntPtr wParam, IntPtr lParam, Boolean& handled)
at System.Windows.Interop.HwndSource.InputFilterMessage(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)

[Jack251970]

It looks like to be problem with system font. Have you changed Windows default font or delete some font resources?

[slickmrick]

Hi & thanks for your reply!
In answer to your question: No, no fonts have been changed/added/removed since FlowLauncher was initially installed and was working fine for a few days until it started throwing up that error in the popup window. After posting the error on this forum, I rebooted the PC and then it was working okay, so maybe the problem will no re-occur. I will monitor it for a few more days, and if the error doesn't come back I will mark this bug report as closed.