Windows 7 desktop has ALL executable files to open with Mozilla Firefox

Greetings wise wizards of EE:

I'm helping a friend with a Dell Windows 7 Pro desktop, that has a very serious issue. According to him, he was working with Avast Antivirus, and while "tinkering", he somehow he managed to set Mozilla Firefox as the default program for ALL executable program files. In other words, when he attempts to open ANY program, including Windows utilities such as System Restore, Mozilla Firefox opens instead. All of the icons on his desktop are displayed with the Firefox log.

The Windows File Explorer does open normally, as well as the Control Panel, but nothing else. He is able to surf normally, but he cannot open any other program. I have encountered this problem before on another machine, though it was Internet Explorer rather than Firefox as the default executable program, and I solved it then by via a reformat & reconstruct the hard drive, but unfortunately I do not have that option here, as he is using some older web design programs, and has lost the installation disks. I have to attempt to restore his machine back to a useful state with all of his current applications intact.

I Googled this dilemma, and it was suggested that a registry modification would do the trick, but the registry editor will not open with the command "regedit".

I would be grateful for any help in this regard.

Many thanks and take care,

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JohnBusiness Consultant (Owner)Commented:
You said you could open Windows Explorer.

Try rebuilding the icon cache.

Please let us know.
☠ MASQ ☠Commented:
See if this will get you back in as of course running an .exe will currently just open Firefox!!
Control Panel->Programs->Default Programs->Set Program access and Computer Default ->Microsoft Windows settings->OK
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Create a reliable backup. Make sure you always have dependable copies of your data so you can restore your entire system or individual files.

zovothAuthor Commented:
Greetings John:

Many thanks for your lightning fast reply, but your solution appears to only address how a shortcut icon is displayed... the heart of the problem is that ALL program executable files open with Mozilla Firefox. In other words, when a program icon is double-clicked, regardless of the application such as Word, Excel, Adobe Reader, iTunes, etc. they ALL just open up Mozilla Firefox.

The issue remains...

zovothAuthor Commented:
Greetings MASQ:

Thanks to you as well for your speedy reply, but I should have posted that I've already tried setting program faults in the control panel to no avail...

The issue remains...

JohnBusiness Consultant (Owner)Commented:
As you note you have a serious issue, so I do not know if the following will work.

Try a Windows 7 Repair install. You need the Windows 7 DVD or a working recovery  partition.
David Johnson, CD, MVPOwnerCommented:
boot from cd, select repair your computerRepair Your Computer Select your Operating System , command prompt
type NOTEPAD and copy the following
Windows Registry Editor Version 5.00





Open in new window

save as fixexe.reg
you can now double click or from the cmd prompt reg add fixexe.reg

reboot computer
☠ MASQ ☠Commented:
And make sure Avast is disabled as that can lock registry settings, wrongly in this case blocking returning them to normal.
Given you can not run anything locally, though it sounds as the impact is limited to your user account versus the entire system.

Using another user account, accessing in safe mode to restore the .exe or actually deleting

In effect following the info change David included...
if you can do a system restore to a time all was ok - it helps you out
zovothAuthor Commented:
Greetings wise wizards of EE:

Today I visited my friend with the Windows 7 Firefox executable issue, and tried the following:
zovothAuthor Commented:
Here's what I tried today, via the link below:

If you notice, this is very similar to the above solution pasted by David Johnson.

I'm afraid this procedure had no effect, but it didn't complete exactly as the above link predicts....

On step 8, I was never prompted with a "Yes" button... or warnings for registration modification warnings. Instead, the DOS prompt simply stated "Operation successfully completed". I then logged off, restarted to no change whatsoever.

I also tried saving the Exe.reg file to his user folder and simply double-clicked on it, and to my surprise, it provided a registry modification warning (rather than Firefox opening), and so I proceeded, then restarted, but there was no change.

I also tried booting to the Windows 7 Home 64 bit disk (though his system is Windows 7 Pro 64 bit), and I choose "Repair your computer" (as shown in David Johnson's post above", and I was presented with the option to "Repair using Windows Tools"; I proceeded, and was then presented with a message "Do you wish to use System Restore to revert to an earlier date?" I clicked yes, but I was never prompted with a date to go back... it simply performed a System Restore in the background, and rebooted to no change. I was unable to run System Restore while booting normally, as Firefox opens any executable file.

I did create another user account successfully, but the same Firefox/executable error occurred.

I am wondering if there is another way to open System Restore, and control how far to revert?

I am also open to any other ideas...

Many thanks in advance,

try starting tit from command prompt, either from the OS, or from the install cd
zovothAuthor Commented:
Greetings nobus:

Many thanks for your reply, but could I trouble you for the instructions on how to do so?


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zovothAuthor Commented:
Greetings nobus:

Hot diggety dog... exactly what I needed... many thanks for the follow up post... I will visit my friend on the morrow, and will try the command prompt system restore.

Thanks again, and I will follow up on posting what hopefully will be a successful restoration.

i hope it helps you out - Good luck Zovoth
zovothAuthor Commented:
Greetings wise wizards of EE:

Many thanks for all of your suggestions, and what eventually found success was accessing Windows System Restore from the DOS prompt, and choosing a date before the problem occurred.

This was a slippery one, and I am very grateful for your help.

Be well and may the wind be at your back,

i feel it !
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