Couple of things I'd like to mention here up front;
A- Do not delete your current 1.0.x installation of Joomla....yet.
B- You MUST have a minimum of Virtuemart 1.1.3 running correctly on your existing Joomla 1.0 site for the migration to be successful. So if need be, upgrade VM first.
It's as simple as uploading a file, and extracting to over write. When you log into your VM admin it notices the updates and runs the DB query bringing your install up to date.
C- You'll also need an SQL file to upload during the migration.
So you'll need to download the latest version of the Joomla Migrator found
here and upload it to your current 1.0x site by using the component installer.
D- Your going to need some Virtuemart plugins for your new migrator in order for Virtuemart to accompany you on this journey. Virtuemart ETL Plugins can downloaded
here.
They can be added to the Migrator by clicking Components > Migrator, and then clicking "add 3rd party plugins" from the bottom of the Migrator screen. This never did work for me.
So I uploaded the zipped plugin package to administrator/components/com_migrator/plugins, and unzipped it there.
E- Now you can go back to your Joomla admin panel and click on components > Migrator, and then "list plugins" at the bottom to verify they are there.
If all is well, click back to get to the front page of the Migrator and click "Create Migration SQL File" from the bottom right.
It'll list the plugins again it's going to create the sql dump for, and at the bottom of the page now you'll see a "start migration" link. You can click that.
The migrator will create the file and go through a couple sequences, and when it's finished you'll be presented with a "MIGRATION COMPLETE" at the top of the page.
Dont be fooled, your migration is far from complete, but your sql file for the migration is complete. LOL. Click the "Download" button in the lower left, and you'll see your sql file listed. You may download it from there.
I suggest saving it to place you can readily find it later. You'll need it soon.
F- Now you may log out of your old Joomla1.0.x, were done there.
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And here we go. Migrating Joomla1.0 to 1.5X and bringing Virtuemart With.
The hype about migrating to J1.5 first and then upgrading to the latest from there seems to be nothing more then that, hype. I've done it from 1.0 to 1.5.12 with no problems.
1- The first thing you want to do is download the latest version of Joomla
here. You'll want the full package and not the upgrade.
2- Create a new directory in your sites control panel and upload the zipped Joomla version you've just downloaded. Do not try to over write your existing 1.0 files with it by placing it in the same home directory.
And yes you'll need to set up a new database for your new J1.5 site.
3- As with any new Joomla install, extract the zipped file, and then visit the url of the directory you uploaded to, to run the installer.
4- When you get to the installation step that asks for your site name, instead of adding that info, scroll down to the bottom, add the table prefix for your old joomla install which is most likely "jos_" without the quotes.
Your old site encoding is most likely iso-8859-1, if not adjust that accordingly.
Then click the browse button to upload the sql dump file you created earlier and downloaded from the Migrator component in your old joomla install.
Finally put a check in the box stating this is a 1.0 migration script, and click "Upload and Execute"
If everything went as planned you'll be presented with a "Migration Successful, please press next to continue and it will ask you for your site name, email and password info again. Fill this out and click next.
Your Done...with the initial install anyway.

From here you can either visit your new site or go straight to the admin panel.
Don't be alarmed if you go straight to the site's front page and things seem a little off. Remember your just migrated to a whole new version and things are much different, plus you'll automatically be set up on a different template. You can adjust things, and add templates later. Right now lets get your Virtuemart content, products etc, working.
The sql dump file you uploaded added all your content from the old Joomla install, and with the Virtuemart plugins, your Virtuemart tables were added to the database.
Now we need to install Virtuemart so you and your viewers can access that content.
This Virtuemart installation process is going to be much different then your old one. So dont just hop over to Virtuemart downloads and think you can download it and install it with the handy component installer within Joomla, and be done.
This gets tricky, so take your time, and be thorough.
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The Virtuemart Part (hey that rhymed!)

Now visit
Virtuemarts download page and download the "Complete Package for Joomla! 1.5".
This is not the typical VM package some of you may used to, so remember you cant upload it as it is. It's actually made up of several more zip files, and again this is where I think most of you are getting confused. Take your time.
1- Unzip the VM zip file to a new directory on your desktop so you can work with the many files within it. You'll notice a lot of goodies in there. Non of it is edible though.
2- Now the first file you'll need to deal with is the "com_virtuemart_1.1.3.j15.zip". You are SUPPOSE to be able to install this as a component through the installer of your new Joomla site, but not as you'd expect.
Inside the admin panel of your new Joomla install, under Extensions is where you install it from but uploading it as a package by using the first option there has been completely ignored by Firefox, and gives fits to Microsoft Internet Explorer.
So your best bet is to jump down to the "Install from directory" option.
Upload the zipped com_virtuemart_1.1.3.j15.zip file to the "tmp" directory of your new Joomla install with Cpanel or what ever you use to access your site files.
Now you can go back to the Admin panel > Extensions > Install/Uninstall, and list the path in the second option (install from directory) and click install.
When it's done it'll take you to a Welcome to Virtuemart panel.
Settle down, were just getting started.
From there be sure to click "Go Directly to Shop". Do not install sample data if you want your prior items to be migrated over.
Go to the the shop, click Admin > Configuration, and then Save. Some tutorials say you need to do this. I do not no if it's necessarily a requirement, but I did do it.
3- This next step is going to be the tough part for some of you. For some reason in all my failed attempts I was never able to actually get the content of my old Virtuemart, products, prices, users etc, to migrate over with the sql dump file.
I know the migrator sql dump creates the tables, so I wanted to make sure the right data was in the tables by exporting my own dump file.
To do that you can go through PHPMyAdmin.
Inside PHPMyAdmin, click the database on the right for your old Joomla install and then choose export from the tabs at the top.
Your presented with a list of tables within that database.
Highlight each of the tables within that list that begin with jos_vm_ by clicking them and holdin your Ctr or CTRL key.
It will be nearly half of them and it'll be the lower half.
Once they are highlighted scroll down and make sure SQL is ticked below the list of tables. Also place a tick under Structure where it reads, Add DROP TABLE / VIEW / PROCEDURE / FUNCTION and then click "GO" in the lower right hand corner.
The next page is your SQL query. Place your mouse inside the window with the text, holding the ctrl key and click A. This highlights all the text.
Now right click the highlighted text and choose copy from the menu that appears.
Now scroll back up and click the home button in the upper left corner.
From there click the database name for your NEW Joomla install.
Once that opens click SQL from the tabs near the top, and you'll be presented with an SQL window.
Click once in the window to get your flashing cursor, then right click and choose paste this time from the drop down menu that appears.
Then click "GO" from the lower right.
4- You can now log out of PHPMyAdmin. The content of your old Virtuemart tables has been copied to your new Joomla database.
Want to take a break? ...or should we keep going going? LOL Were almost done.
5- Now we go back to the admin section of your new Joomla site. Were going to install some more pieces of that so called Complete Virtuemart package you downloaded and unzipped to your desktop earlier.
Go to Admin > Extensions > Install/Uninstall
The rest of the uploads done through your admin panel will play nice with Firefox and M.I.E., so were going to use the first option in there which is "Upload Package File", from now on.
Click browse and find the file inside your unzipped VM Complete directory titled mod_virtuemart_1.1.3.j15.zip. It's going to be inside the modules directory of that unzipped VM package and along with about 12 other zip files, so take your time.
Then click upload and install.
6- Now you should go to Admin > Modules, and enable the Virtuemart Mod you just installed, by clicking the red X to the right of it in your module list.
7- Now you can go back to Admin > Extensions > Install/Uninstall, and in the same fashion as you just did, finish uploading and installing all the remaining files within the module directory of that VM complete package.
Be sure to go back and enable them when your finished with them all. As described in step 6
8- Once your done with that, done the same way, you can upload and install the two files found within the "Plugin" directory of the VM Complete package.
Your Done!
If everything went right, and it certainly should, your cart should now be fully functional as it was before, but with tons of new features and a whole lot easier to use.
You can now start to rearrange the modules and content on your sites front page to suit your needs, since it most likely will not be a replica of your old site, due to the fact that the templates will be different.
The only thing that may not have migrated over for you regarding your Virtuemart install would be the images. Meaning product images, category images etc. And those can easily be copied over with your Cpanel by copying the entire directory components/com_virtuemart/shop_image/product directory to your new install and over writing the existing one with your old one.
Just be sure to place it where it goes by following the same path.
Once you've finished tweaking your site and making all the adjustments needed to make it presentable, you can remove your old version by moving all the files to a different directory in case you find you need something later, and then moving the new install to it's directory.
You'll have to edit a couple paths in your config file to match, but it's easily done.
If this tutorial helps 1 person, I'll consider it time well spent to set down and type it out.
I fought with this migration for weeks before finally figuring it out, and personally I think the tutorials out there, what few of them there are, leave out too much information, that a lot of them are taking for granted folks know.
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ADDENDUMS<--
** Virtuemart applications using PayPal payment methods
The PayPal information, (your PayPal address) doesn't seem to be following along with the migration. Most likely for security reasons.

Never the less, you will need to re edit your PayPal configuration once migrated. Which also includes removing the PayPal payment method from 'test mode'.
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** Some servers and some zip files may have a tendency to NOT retain their appropriate permissions when extracting.
Which means that if you upload a zip a file to overwrite while either doing your migration or when putting the finishing touches on your new 1.5.x site, you may find that all of a sudden your faced with server errors, or page denied etc.
Before you panic, and uninstall, or delete everything, there's a 98% chance that this is simply a permissions issue caused by the zip file you just extracted to overwrite, not retaining the proper permissions.
If you are running either Suphp or Suexec, or both, on your server or your host is, this is especially true.
Go in through an FTP program WinSCP or something similar to check or re-edit permissions. Dont rely on Cpanel or Plesk to show you the right permissions due to caching issues especially if you've just overwrote the files.
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