Hi

Thank you for your question.

It is a little unusual to hear of someone dual booting two versions of Windows, most people would probably backup and port over their data. As a result I am not sure about the ability to interoperate both platforms.

Trying to make both copies of Firefox use the same Firefox Profile could be problematic, but one option you may wish to consider is using Firefox Sync. This is not a backup medium, but can help in copy bookmarks between two copies of Firefox.

I hope this helps.

Using Sync is probably what most people would do.

Just a caution on using Sync. Personally I stopped using it because it had a tendency to corrupt bookmarks files (That is well documented fact). So if you do use Sync I suggest you make sure you manually backup your bookmarks on a regular basis, it makes it a lot easier to recover from any corruption.

I have various multi boot systems but avoid using Sync and most of the time just copy the bookmark files (places.sqlite) between various partitions and profiles)

See also

• Restore bookmarks from backup or move them to another computer_manual-backup
• Back up and restore information in Firefox profiles
• Recovering important data from an old profile
• Profiles - Where Thunderbird stores your messages and other user data
• Moving Thunderbird Data to a New Computer

P.S Note the export as HTML option may be used to add bookmarks and does not overwrite existing ones. Sync is totally non directional. Using the HTML copies it is easy to add a set of small bookmarks to a larger collection. The HTML files are also easy to edit on for instance WordProcessors

• Export Firefox bookmarks to an HTML file to back up or transfer bookmarks
• Import Bookmarks from an HTML file

Actually from what I read about Sync frightens me about lost data. I The reason that I am still using Windows XP is because of my business contracts and their related protection. These types of contracts are the ones that have you fingerprinted and investigated. By law I must keep these for ten years. So I will keep on using XP for the foreseeable future. So with an eye on the future I installed Windows 10 Pro. Over time I will wean myself away from XP until I no longer use it. THat is why both systems.

Maybe a better or clearer question would be: How can I force Firefox (and profiles) to look in a directory other than what Firefox selects by default? The answer to this would also apply to Thunderbird and for the same reasons.

Thanks to both of you. I managed to find a solution on my own and it is surprising simple, for Firefox as I have not tried it on Thunderbird. All I had to do in modify two lines for each profile in the PROFILE.INI in the \Mozilla\Firefox directory. It is as follows, changes are in italics:

[General] StartWithLastProfile=1

[Profile0] Name=AnyName IsRelative=0 This is a switch and change it from 1 to 0 to turn off Path=Type full path here starting with the drive ending with the profile.suffix Default=1

[Profile1] Name=AnotherName IsRelative=0 Path=Same as above

[Profile2] Name=AndStillAnother IsRelative=1 Path=same as above, and so on.

Now no matter what OS I am using the files are updated when using either.

Well done for finding the info, but please note you need to take care. I personally would not go down that route. I consider it unwise & likely to cause problems at some stage.

Now no matter what OS I am using the files are updated when using either.

NO they are not unless you use Sync !? Or are sharing profiles !!!

If you try using the same profile for two separate Firefox's you will inevitably run into trouble.

Also if you are dual booting Windows I wonder how you can see the same profile from each boot. (Maybe it is a Windows VM or a Separate Data partition)

I often have many installs of Firefox of various versions (and eqivalents IceWeasel IceDrgon, PaleMoon) and have learnt it is sensible to never share profiles. Clone them by all means and have multiple profiles for Firefox installs. One:many is ok Fx:Profiles but not Profiles:Fx

I often manually create profiles, but note you can do it with better safety from within Firefox, or by using a standalone profile manager {I presume that is still available and supported,I have not used it for a couple of years).

• Stand alone profile manager: https://developer.mozilla.org/docs/Profile_Manager

Maybe a better or clearer question would be: How can I force Firefox (and profiles) to look in a directory other than what Firefox selects by default? The answer to this would also apply to Thunderbird and for the same reasons.

On this forum we do not document use of multiple Firefox profiles, other than for troubleshooting, but Mozillazine does document it as you may have discovered.

• Built in profile manager: Profile Manager - Create, remove or switch Firefox profiles
• http://kb.mozillazine.org/Using_multiple_profiles_-_Firefox

As for Thunderbird see

• Profiles - Where Thunderbird stores your messages and other user data
• Using Multiple Profiles

Oh, and take care with the built in profile manager. Best not to use it to rename profiles because it renames the profile but not the directory, that can easily lead to confusion and accidental deletions.

Windows XP is because of my business contracts and their related protection. These types of contracts are the ones that have you fingerprinted and investigated. By law I must keep these for ten years.

I do not want to go outside the scope of this forum. This is not a place to discuss security issues. However I am rather concerned that an unsupported XP even with current Firefox may have security issues.

Do you really want an XP connected to the Internet to have access to your Windows 10 data and directories !!? sounds like a gaping security hole.

Thanks everyone for the feedback and concern. When I am talking profile here it is limited uniquely to Firefox not Windows.

When you mentioned

  Now no matter what OS I am using the files are updated

when using either.

NO they are not unless you use Sync !? Or are sharing profiles !!!

Actually I am not sure in this instance what you mean by sharing profiles.

Anyway I deliberately loaded data with FF using either Win XP or Win10 and as expected after about six hous of switching back and forth between OS the files are updated accordingly and accessible by FF operating in either OS. Remember that in my instance only one Windows OS can be loaded and functioning at any one time.

For me I must power off and "RESTART" to load (boot) the alternate Windows. So whether I boot XP and access FF profiles on Drive G:\ or power off and boot to W10 and access the same files on drive G:\ the files are being updated by either one or the other, but not both. Impossible to do.

As far as being secure, I like many others am cautious, The last time my XP was updated for "Malicious Software" was on January 12 , 2016 under Microsoft number KB314540. I still receive these regularly. Plus for my contracts I was compelled to have three System Securities installed one active and two passive. All are updated hourly as long as I am on-line. When away from my PC the firewall is set to block all incoming/outgoing.

As you stated what works here with FF should also work with Thunderbird. That is really my objective. Not this. This is only the practice run at the real thing, TB. I have records in Thunderbird (Netscape before) dating back to 1995. But I will let the results that we have discussed here with FF proven themselves as robust and secure before I perform the same thing with TB. Likely take several months.

Thanks for the help, the answers and for stimulating even more though into this.

I hope the example of a profiles.ini file that you posted isn't the formatting you used. The [Default0] portion shows empty lines where none should be.

This is the correct format, no spaces between for script for each Profile.

[Profile0] Name=AnyName IsRelative=0 Path=.... Default=1