It's pretty simple. Batch files can be used to submit DOS commands to windows, like when you change your MTU with command prompt, it basically does just that.
Assuming you already know what MTU is and how to use it... I'll continue assuming you have that knowledge, if you don't I suggest you search
"Lag" on the wiki. Find the mtu section and use what applies to you.
Step 1). Open notepad...
Step 2). On the first line add the command that applies to you. In my case that's this: netsh interface ipv4 set subinterface "Local Area Connection" mtu=386 store=persistent
Step 3). Second line, exit the program with "exit;"... unless you want the CMD window to remain open which I'd assume you don't.
Finished product looks like this:
[CODE]
netsh interface ipv4 set subinterface "Network Connection" mtu=386 store=persistent
exit;
[/CODE]
Step 4). Save As whatever name you want just make sure file format is .bat
To do this simply change the "Save as type" from text documents to Any file type. This will allow you to add .bat to the name of the file. Example: MTU386.bat(this is what mine is saved as lol)
I can't stress enough how important checking out the Lag page on the wiki is if you don't understand MTU.
Also... you're gonna want to have a second file for reverting your MTU back to 1492.
That looks like this...
[CODE]
netsh interface ipv4 set subinterface "Network Connection" mtu=1492 store=persistent
exit;
[/CODE]
Mine is named to MTU1492.bat
Additional reminder: These files MUST be ran as admin, otherwise it's likely to not work.
Batch files are very powerful tools that can be used for much harm. Especially if you're using one you have no idea what the content of it is. As Bunny said OP, posting that as a file wasn't the best idea. This process could have been easily explained if you are a "Computer Technician" as you say. You should be well aware that people on gaming related forums will always be wary of files, especially from members with low post count.
Have a nice day everyone and happy MTUing! :)