Upgrading Drupal

I have a multi-site installation using a Drupal common code base: "mydomain.org" in fact has multiple sites, one for each language (eg, en.mydomain.org for English, fr.mydomain.org for French, bn.mydomain.org for Bengali, etc). Each subdomain is redirected to the directory where the common code base is installed - since I'm in the middle of an upgrade from 4.6 to 4.7, some subdomains point to a directory called 460/ with the Drupal 4.6 codebase, others to 470/ with the 4.7 codebase (and there is even a brand new site which was built directly in 5.1 and which points to 500/ with the 5.1 codebase).
In this situation, the upgrade process so nicely described by the Lullabot video simply does not work, for two main reasons:

1. The process involves an upgrade in situ, in other words overwriting the site's existing code base. This is not acceptable because if I overwrite the codebase for one subdomain, I automatically overwrite it for all the others as well
2. The only way around that would be to upgrade all the sites in one go. However, given the number of sites, and the amount of reorganisation that is being done as part of the upgrade process, this is simply not a realistic proposition

Hi,
I upgraded my site to drupal 5.1 a few days ago and since then i have been unable to add images to my site. Today after some troubleshooting with my hosting provider, we figured out that the problem was with the sapces in filenames ie if there were spaces in filesnames then the image will not be displayed whereas any other file without any space in the name worked wothout a problem.
I never faced this problem with drupal 4.7.6

Can someone help please

Hello, ok am trying to do a 5 to 5.1 upgrade, have followed instructions, including upgrading modules but when i run update.php i get DB errors for Tinymce?

Hi,
Like many other users of Drupal, I upgraded my site to drupal 5.1 a few days ago. since then I have started having problems with images. Some of the images from the site are not showing and only a text is showing in their place and some are working just fine.
The other issue is that no user including the admin are able to add any new images to the site. If we try and add any new image, only the title of the image shows and thats it. This problem has been reported on several posts but no solution has come thus far.
The posts where the problem has been reported are

Hello,

My team has designed and deployed three sites on campus that use Drupal - all have been very successful and well used. We pointed out to the web services folks last week the upgrade to Drupal and the security issue it resolved. Their response was to call me in to suggest that I move away from Drupal as it is "too difficult to make multiple instances / sites" - they want something easier to achieve this as we wish to grow the number of Drupal sites running on our server(s).

If I am looking at things correctly the regexp used in system 178 upgrade (that adds the "/" to links during the 4.6-> 4.7 upgrade) is missing the capability to upgrade links which have apostrophes rather than quotes. The code only upgrades href="..." NOT href='...' - which is what I expereinced during my upgrade.

Instead of =\" I believe that should have =(\'|\") to handle either setting???