When using ReadAllText method to read a log file with a size of 21.83MB, it takes between  7 seconds (for powerful CPU) to 12 seconds (for weak CPU).

Dim file As New FileInfo("path\to\file")

Using reader As StreamReader = file.OpenText()
    While Not reader.EndOfStream
        Dim nextLine As String = reader.ReadLine()
        ProcessLine(nextLine)
    End While
End Using

Const MAX_BYTES As Integer = 1048576 * 5 '=10 MB 
Dim bytesRead(MAX_BYTES) As Char
Dim numBytesRead As Integer
Dim currentPos As Integer = 0
Dim strFileName As String
Dim strm As System.IO.Stream
Dim TextLine As String
Dim FileDetail As IO.FileInfo

OpenFileDialogMain.ShowDialog()
strm = OpenFileDialogMain.OpenFile()
strFileName = OpenFileDialogMain.FileName.ToString()
  
Using reader As System.IO.TextReader = _
System.IO.File.OpenText(strFileName)
  numBytesRead = _
reader.ReadBlock(bytesRead, currentPos, MAX_BYTES)
  TextLine = reader.ReadLine()
End Using

txtEditor.Text = New String(bytesRead)
txtEditor.Text += TextLine
txtEditor.Text = txtEditor.Text & vbCrLf & Now

Test Methodology

Conclusion: stick with ReadAllText method to read a log file.

Whenever you see this error message

“Cannot open [Windows service name] on computer “

you need to run the VB.Net code as an “Administrator”. There are 2 solutions available.

Solution 1: Modifying “app.manifest”

1. Go to project and select “(Project Name) properties…”
   
2. Click on “View UAC Settings”
   
3. Find the code “<requestedExecutionLevel level=”asInvoker” uiAccess=”false” />”
   
4. Replace the code with “<requestedExecutionLevel level=”requireAdministrator” uiAccess=”false” />”
5. You will be able to run your sample code now.
6. Later, when the code is compiled to executable (exe), this VB.Net application will also run as “Administrator”.

Source:

• http://www.downloadinformer.com/how-to-make-a-vb-net-application-always-run-in-administrator-mode/
• https://www.codeguru.com/vb/gen/vb_system/accessing-administrative-privileges-from-your-visual-basic-programs.html

Solution 2: Running Visual Studio as an “Administrator”

Step 1: Find Visual Studio IDE in program files, for my machine it is located at “C:\Program Files (x86)\Microsoft Visual Studio 9.0\Common7\IDE”

Step 2: Right click on “vbexpress.exe” and select “Properties”

Step 3: Click on “Compatibility”, then check on “Run this program as an administrator” , then click “OK”

Step 4: Run the program and it will run as administrator.

Applies to: Intel Graphics HD 5500.

Solution: upgrade to latest driver from Intel web site or using “Intel-Driver-and-Support-Assistant-Installer.exe”.

Problem: If the the post with video attached is edited, even though I did not remove the video, the video will be automatically removed.

Solution: none.

Problem:

1. The default administrator account has problem with uploading video
   
   and accessing “Video library”
   
2. The above 2 errors occurred when used in:-
   1. Opera browser Version:68.0.3618.125 in Asus laptop
   2. Chrome browser Version 83.0.4103.61 (Official Build) (64-bit) in Asus laptop
   3. Chrome browser Version 81.0.4044.138 (Official Build) (32-bit) in  Dell-E6410 laptop
   4. IE 11 in Asus laptop

Solution: add another FB account as “Administrator” and able to solve the above roblem — able to access “Video library” and successfully upload video.

(T, please add here …)

Machine: Asus UX303

OS: Windows 8.1 64-but

Status as at 2020-05-25:  fail to solve

1. sfc /scannow returns this message — “Windows Resource Protection found corrupt files but was unable to fix some of them. “
2. Run “DISM” as follows:
   1. Type “cmd” in windows search bar
   2. Right click on “Command Prompt”
   3. Select “Run as Administrator”
   4. Type “DISM /Online /Cleanup-Image /CheckHealth” without quote and press ENTER
   5. Type “DISM /Online /Cleanup-Image /ScanHealth” without quote and press ENTER
   6. Type “DISM /Online /Cleanup-Image /RestoreHealth” without quote and press ENTER
      (source: https://answers.microsoft.com/en-us/windows/forum/all/sfc-scannow-found-errors-but-couldnt-fix-all-of/663ec1fa-a215-41b8-abbb-2aa1cca703e2)
3. If “DISM /Online /Cleanup-Image /RestoreHealth” return this message — “The source files could not be downloaded. Use the “source” option to specify the location of the files that are required to restore the feature.”
   then
   1. mount the “iso” file of the Windows
      (the “iso” file is mounted as “E:\” drive)
   2. Type “DISM /Online /Cleanup-Image /RestoreHealth /Source:E:\” without quote and press ENTER
      (source: https://www.thewindowsclub.com/dism-fails-source-files-could-not-be-found/ )
4. Same error message appeared — “The source files could not be downloaded. Use the “source” option to specify the location of the files that are required to restore the feature.“