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Anytime I try to start up QBasic 4.5 on Windows XP, I get an error stating "Invalid startup directory, please check your pif file. Choose 'Close' to terminate the application." I know that this is a 16bit MS-DOS Subsystem, but this is the only program I am having trouble with. I recently upgraded to WinXP Pro, and needless to say, I was quite surprised when I couldn't write my programs anymore.

Boy... now there's a blast from the past. QBasic has a long history dating back to the days of MS-DOS. QBasic was the free Basic programming language interpreter that was included with MS-DOS, and eventually Windows, though it appears to have vanished from Windows XP, if not from earlier versions.

I feel a personal connection to QBasic. Why? I worked on it!

First, your question: ".PIF" files were the way that older versions of Windows kept track of the settings for some applications. Each application, say QBasic.exe, would have a corresponding PIF file, such as QBasic.pif.

"QBasic was the free Basic programming language interpreter that was included with MS-DOS"

In Windows XP, I believe it's safe to simply remove the QBasic.pif file. Try renaming it first, and seeing if that resolves your problem. You can also try right-clicking on the PIF file in Windows Explorer, selecting Properties, and changing the startup directory, that your error message is complaining about.

I dug up an old copy of QBasic and fired it up, without a .PIF file, on my Windows XP system:


Like I said it brings back memories. While at Microsoft I worked on the on-line help technology used in QBasic's predecessor, QuickBasic, several other products, and in QBasic. Need proof? In a command shell, Type the on-line help file qbasic.hlp. The first two bytes are the "signature" that define what kind of a file this is. The signature for character mode help files? My initials: LN.

Article C2480 - December 5, 2005 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

March 10, 2006 7:02 PM

Is it safe to delete Qbasic.pif on Windows 98?

March 11, 2006 9:40 AM

Should be ok. Copy it somewhere else as a backup, just in case.

Tom Green
July 7, 2006 1:50 PM

I have been using an old MS-DOS word processing program called WordStar 2000 (WS2000) and have probably over 1000 files in several hundred client folders. The programs work fine on my Windows 98 desktop but I recently bought a Dell laptop with Windows XP and copied the WS2000 program and all of my WS2000 folder to the new laptop. When I try to access WS2000 on my lap top I get the error message, "Invalid startup directory, please check your PIF file". WS2000 still works fine on my Win98 desktop. Is there some way that I can get WordStar 2000 to work on my new laptop? I am not a computer guru so I don't understand all that I read above. My real question is, does the article above apply to me. If it does, I will take the article and my laptop to a computer place to have them fix it. Thanks for your help. - Tom Green

July 8, 2006 5:41 PM

I, too, used Wordstar. :-)

Yes, the article applies. I'll bet you have a .pif file in the same directory as the Wordstar .exe file. Delete that and I'll bet you're good to go.

November 17, 2006 7:22 PM

Free basic is a great resource for running/writing basic programs on XP systems. The FBIDE interface is also highly recommended. Better than the original Qbasic.

December 14, 2006 5:40 PM

When i start my computer, this appears C:WINDOWS\DEFAU I.PIF

and C:WINDOWS\o4243127.exe

What does this mean? Can you help? I use Windows XP.Thank you....

Leo Notenboom
December 22, 2006 10:00 AM

Looks like a virus or spyware to me. I'd scan for both.

May 31, 2007 6:16 AM

When i go install battlefield 1942 it says 'Invalid program file name please check your pif file Choose 'Close' to terminate the application someone please help.

August 2, 2007 12:32 AM

When i start my computer, this appears C:WINDOWS\DEFAU I.PIF and after that this msg appeared "Invalid startup directory, please check your pif file. Choose 'Close' to terminate the application."...wuts going on actually with my computer?..and computer hang suddenly..someone please help me..T_T

November 17, 2007 12:55 AM

I am trying to get into my business folder and then "Invalid startup directory, please check your pif file. Choose 'Close' to terminate the application." Can you please tell me what to do? Thank you

August 16, 2008 3:07 PM

when i try to open qbasic 4.5 it says to check my pif file how to I do that? also how to i change my startup directory?

November 22, 2008 2:46 AM

Dear sir,
this is mohsin from dubai when i try to start my game prince2 then coming error ( invalid startup directory please check you pif fil. choose close to terminate the application. please help me thnks

Adrian Henderson
May 30, 2009 7:23 PM

I deleted the pif files, it works so far. PIF files are the MS-DOS icons. When in doubt, search "*.pif," and delete corrisponding (speeled rong) .pif's from your QBasic directory.

September 3, 2010 2:11 AM

My problem is a moody Turbo C++ program. I got the same error message. So I cleaned out all of the guilty pif files. What do I do now? How do I start it up?

September 5, 2010 2:28 AM

I found the pif file - QB [Surprisingly it did not have the extension '.pif' in the name, although I do not hide extensions]. In Properties > Program I set the 'Cmd line' to the correct path to the file, and 'Working' to the correct path to the folder. That solved the problem.
I also ticked 'close on exit' here, & 'window' under Screen. Under 'Memory' I set 'EMS' to 'none', 'XMS' to 'auto' and ticked 'use HMA'. That made it work better I think.

January 1, 2011 11:50 AM

Thanks for your help! I no longer get the error, but now the game won't run. It seems to run for a fraction of a second, and then disappears. Anyone know what I'm talking about?

July 23, 2011 8:10 AM

hi sir i wank your kind info from one question??????

i was opened TURBO C++ wizard . its warmed as unrecoverable error , why this error found plz reply me

fred smith
December 13, 2011 11:24 PM

Thanks; renaming qb.pif by dropping the .pif extension, worked.

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