Error while trying to save .dds files

[FastRacer023]

Since yesterday, whenever I try to save a .dds file this error occurs:

 

Application version: paint.net 4.2.8

System.IO.IOException: Εσφαλμένη λειτουργία.

   at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
   at System.IO.FileStream.WriteCore(Byte[] buffer, Int32 offset, Int32 count)
   at System.IO.FileStream.Write(Byte[] array, Int32 offset, Int32 count)
   at PaintDotNet.IO.GuardedStream.Write(Byte[] buffer, Int32 offset, Int32 count) in D:\src\pdn\src\Base\IO\GuardedStream.cs:line 442
   at DdsFileTypePlus.DdsNative.StreamIOCallbacks.Write(IntPtr buffer, UInt32 count, UInt32* bytesWritten)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at DdsFileTypePlus.DdsNative.Save(DDSSaveInfo info, TextureCollection textures, Stream output, DdsProgressCallback progressCallback)
   at DdsFileTypePlus.DdsFile.Save(IServiceProvider services, Document input, Stream output, DdsFileFormat format, DdsErrorMetric errorMetric, BC7CompressionMode compressionMode, Boolean cubeMap, Boolean generateMipmaps, ResamplingAlgorithm sampling, Surface scratchSurface, ProgressEventHandler progressCallback)
   at DdsFileTypePlus.DdsFileType.OnSaveT(Document input, Stream output, PropertyBasedSaveConfigToken token, Surface scratchSurface, ProgressEventHandler progressCallback)
   at PaintDotNet.Data.FileTypeProxy.OnSave(Document input, Stream output, SaveConfigToken token, Surface scratchSurface, ProgressEventHandler callback) in D:\src\pdn\src\PaintDotNet\Data\FileTypeProxy.cs:line 69
   at PaintDotNet.FileType.Save(Document input, Stream output, SaveConfigToken token, Surface scratchSurface, ProgressEventHandler callback, Boolean rememberToken) in D:\src\pdn\src\Data\FileType.cs:line 282
   at PaintDotNet.Controls.DocumentWorkspace.<>c__DisplayClass248_0.<DoSave>b__5() in D:\src\pdn\src\PaintDotNet\Controls\DocumentWorkspace.cs:line 2852
   at PaintDotNet.Functional.Func.Try(Action f) in D:\src\pdn\src\Base\Functional\Func.cs:line 174

Does anyone know how to solve it? I can use the save as function, but I can't overwrite files

[BoltBait]

4 hours ago, FastRacer023 said:

I can't overwrite files

 

Are the files being held open by another program or window?