There were some suggestions on the last post https://support.mozilla.com/en-US/questions/772295

What sort of files are you trying to open eg music files?

Can you see the full fileanme including the file extensions ?

I am not a Vista user but does Vista let you right click a file or shortcut and then allow you to choose what to open it with ?

Hello John 99,

Thank you for your kind reply. The files I could never open over the last 4 days were .exe files, which run all sorts of programs, etc. The same message box kept recycling over and over: "You have chosen to open..." and always gave me only 2 options--either save or cancel; and then a tab called Untitled would pop up on top of my regular window accompanied by a blank page in the window itself!

I experienced almost a full shutdown of my files and programs ( I still managed to get and send e-mails). I could not even get System Restore to do anything but offer the same "save" or "cancel" message that had no options to open.

I finally figured out that by pressing F8 before my logon screen came on I could get my hard drive to repair itself--offering a list of programs I could attempt for salvage. This time I entered System Restore and chose a restore point from 10 days back. And blessedly it opened the restore point without being circumvented by an ignorant message box! So Hallejuja! and Merry Christmas! Everything works again, including my .exe files.

Still don't know what caused the nonsense--I use Malwarebytes Antimalware and Norton 360 security, which displayed a virus-free, Trojan-quarantined PC.

Thank you, again, John99, for your suggestions. Sincerely, marlem388

Hi Marlem,

I am glad you seem to have solved the problem.

You may be interested in this article:How To Change the Default Program for a Specific File Extension in Windows Vista

It is less drastic than using restore points, and may help if problems re-occur.

John99,

Yes, now I have read through "How To Change the Default Program for a Specific File Extension in Windows Vista." Thank you for that alternative prospect. I'll try to use it should this glitch stymie me again.

When I looked through my default file associations I did find .EXE (it was the only one with another punctuation mark added--a comma after the extension letters--so it looks like this: .exe,--don't know if that makes any difference).

But here's the rub: the program that opens my .exe is "Windows Live Photo Gallery" (?). Which may or may not be appropriate--I'm not sufficiently familiar with the dynamics of any program to know how efficient it is for a particular app.... So am loathe to change to some other program that might destabilize the .exe extension, which seems to be doing all right now (so far).

I very much appreciate your responses and am glad to know that I could at least try to use another program (when I figure out which one!) in order to open that particular file instead of doing the nasty drastic.

Sincerely, marlem388

■ Punctuation is important

In most computer code etc. punctuation is important. In earlier times MS & Windows file names were limited to a 8.3 format of eight characters, a dot and three characters; there were also restrictions on what characters could be used, and whether upper case or lower-case was permitted I am guessing if you have some odd .exe, showing up with a comma on the end it is possibly something that was somehow misnamed.

■ Executables and .EXE

There are broadly speaking two categorises of files

1. Executables such things as firefox.exe, or the main Windows explorer (that allows you to navigate your computers desktop and folders) explorer.exe such files either run by themselves or with the help of other files. One often would be unwise to change these extensions or their associations. Some others to be careful with might include .com .bat .dll .css
2. Data/ content such as a document.txt picture.jpg file or webpage.htm now with this sort of file the user of a computer may want to choose which application or program is to be used on that data.

• EXAMPLE If you choose to set firefox as your default browser you will find it opens most .htm files on a windows system, instead of the default Internet Explorer being used. You do not need to change this using Windows OS, you can do it from within firefox itself, see Make Firefox your default browser. Once you have done this you will notice that .htm files have become associated with the program firefox.exe

■ Firefox & content files

• Use Tools -> Options -> Applications

that will show you what firefox is using to open content files, although note you need to differentiate between content that is a self contained file of for instance .jpg type, and content that is embedded within a webpage. see

■ Viewing pictures; Image Files eg .GIF & .JPG

Two common types of image files are .gif & .jpg or .jpeg such files are often used on computers, and sometimes embedded within webpages. Although I do not use Windows Live Photo gallery I would guess that if you do that is set to open many image files and its program name will, on your system, be associated with .gif & .jpg files. There are alternative picture viewers available. I can open both .gif & .jpg types of file, that are saved on my computer, in a firefox tab for instance. I presume such files types are supported natively in firefox without needing any addon.

Dear John99,

Your persistence in helping me address my .exe snarls is magnificent and non-pareil ! I am grateful for it.

Actually I made Mozilla Firefox my default browser a couple of years back. And I have tried through my Control Panel to make Firefox the default program for opening all files too. (Have tried to do this several times.)

Regardless, whenever I check my default program entry within my Control Panel window, the space wherein I placed Firefox is always blank!

All very, very weird.

Now, per your advice, I also invited .regfix to Windows Vista HomePremium (got it from Winhelponline.com--Webs of Trust and Norton Safe Search both assured me it was a trustworthy site).... But when I restarted my PC and looked in the files associations window--UGH--there was the old deranged file extension name: .exe, (with its crooked little comma!) rearing up like a leetle vampire. I'd put a stake through its leetle black heart if I knew how.

Also visited one of your link suggestions on Firefox called "Adding Download Actions." Noticed that my download messages never pop up with an "Open with" option; the message window shows only a "save" or "cancel" option. ...I'd like to have an "Open with" option; how canI get it?

I'm hoping now that I've merged Vista with .regfix, things will be facilitated no matter what my Control Panel coughs up.

Again, John99, you have been wondrously observant and tirelessly helpful. I'm just afraid that my OS doesn't deserve you or is too dumm to understand.

Blessings, marlem388

■ errant file extension .exe, with trailing comma

I would not be too concerned about that especially if you are not to certain what or where it is, it probably does no harm, and as I speculated previously is probably something mis named or mis edited.

■ Firefox as default program for all files

I am not sure: And I have tried through my Control Panel to make Firefox the default program for opening all files too. (Have tried to do this several times.)

• if you succeed in that you recreate the original problem of paralysing your computer because everything tries to open in firefox

that one would want firefox to open all files, certainly not as the default program. Think about the following tasks

• ordinary operation of the computer !
• writing and editing a complex text document or a spreadsheet
• editing a video or photo image
• designing a webpage

I think many users would consider doing such tasks with something other than Firefox.

remember even if your OS or Vista control panel says firefox is not the default program for opening a certain file it is still possible to open supported files with firefox. (sometimes that will need add-ons). You will also at least to some extent be able to browse your local hdd, try for instance using in the location bar ///C:/ Or just find a file in Vista right click then open in firefox and bookmark it. (possibly using something such as a webpage you have just saved from firefox to your computer)

Hello yet again, John99!

--OK, seems my OS is not the dumb one then. Good thing I wasn't able to open all my files in Firefox; thanks to you I understand now what that means. No, I sure do not want to use Firefox for everything, and Vista was astute enough to ignore my attempts.

And yes, I did have just enough savvy to select Firefox to open those files it supports best; those I relegated to Firefox's mastery.

Thank you very much for all your fine advice, especially for clarifying the last crux of my dilemma.

Grateful for your diligence and expertise, John99. marlem388