When I try to execute my jar file through the command prompt by typing:
java -jar myJar.jar
It returns an error message saying that it can not access the jar file. Why is this? myJar.jar is the exact name of my jar file.

Where is your jarfile and where are you trying to do that?
And what's your classpath?

my jar file is MyJar.jar located at C:\Documents and Settings\Josh\My Documents\JAVA Programs.
My Class path is payroll, The jarfile and manifest files are all correct I believe.
I am trying to execute 'payroll' through the command prompt.

you'd have to be in that very directory then. And add '.' to your classpath and path.

how would you get into that directory?

Hi everyone,

Do this list what is in your manifest file here. Also list exactly what you are typing on the command line with all the full path and class path so we can see what's wrong

Richard West

I am sure that my jar and manifest files are correct:
Manifest-Version: 1.0
Created-By: 1.4.2_04 (Sun Microsystems Inc.)
Main-Class: Payroll


I was typing in the command prompt: java -jar myJar.jar
it returns 'unable to access jar file.

my jar file is myJar.jar located at C:\Documents and Settings\Josh\My Documents\JAVA Programs.
My Class path is payroll

Hi everyone,

Do this

java -jar -cp .;C:\Documents and Settings\Josh\My Documents\JAVA Programs myjar.jar

I haven't run java programs from the command line for quite some time but i think this is it. Someone correct me if i am wrong

The manifest file looks correct.

Let me know if it works

Richard West

hmm.. when I type that in it says 'Unable to access jarfile and'
Maybe its because the starting prompt says: C:\Documents and Settings\Josh> ?

Hi everyone,

hmm.. when I type that in it says 'Unable to access jarfile and'
Maybe its because the starting prompt says: C:\Documents and Settings\Josh> ?

The starting prompt needs to be the location of java.exe

Richard West

Hi everyone,

The starting prompt needs to be the location of java.exe

Richard West

No it doesn't. As long as java.exe is on the path you're fine.
And that's not his problem anyway. His problem is a path problem where he can't find a jar he tries to launch.
So all he needs to do is call java with the correct location for the jar, which he doesn't seem capable of doing for some reason.

A beginner's course in using a command prompt might be in order :mrgreen:

Hi everyone,

You have to forgive me for the wrong code as i have not run jar files from command lines since 1998 but this is what you need to put exactly on the command line.

Say your jar file is at "C:\Josh.jar"
Say your java.exe file is at "C:\java\bin\java.exe"

Type this exactly

C:/java/bin/java -jar C:\josh.jar

remember that the -jar has a space on either of its side and for the java.exe don't include the .exe

I usually try to run my jar files programatically using the Runtime class as with that i can get both the error and output stream of the runtime.

Let me me know how it works out

I hope this helps you

Thank You

Yours Sincerely

Richard West

Member Avatar for joankim

Hey. I know this thread is EXTREMELY outdated, but it is still almost at top at google, and I did not find this solution anywhere else online. I just changed the starting prompt location to the folder in which the jar file is located. For example, if your jar file location and name is: C:\Users\Tod\file.jar, you can do two commands:
cd C:\Users\Tod

java -jar file.jar

This worked for me, hope it helps!

hey Joankim it also works for me but my question is why ISN'T java -jar -cp "c:\xxxxxxxx"MyJar.jar working from command prompt.

Harvey_1 :
you could/should have posted that in a new thread. this is what we refer to as a 'dead thread', a thread that is years old, and marked 'solved' almost a decade ago. chances of people reading this are slim.

start a new thread, provide all the information of your specific case, and ask your question there.

^ to answer to the person above me, i happened to find this thread pretty useful and considering how it is decade old but still on google top search for this issue, its amazing, Anyway, thank you guys for all your help.

John: seriously, there is no need at all to revive dead threads. This will still pop-up in google, or by just using the search button on the top right.
If you only consider top-google results as resources, I recommend a different carreer choice.

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