Yet, I am told the following:

You do not have access rights to complete this operation.

WARNING: for legal reasons, only the owner of the domain can activate the blog associated with the domain

I am logged in using the Gandi handle shown as being the owner handle on the main management page for my domain (since I own it), and I can not create a blog. I'm hesitant to start a support ticket to have it go unanswered. However, I do not wish to wait months for an answer to this question that may never come by posting here, either.

Here we are in 2011 and I just had the same problem. This was when I was trying to create a Gandi Dotclear blog, but it involves domain ownership rights, so I think it relates to your situation. Here is what transpired.

For the purposes of this reply, I am making up the gandi account numbers:

RG9999 = the account I thought I always had and the only one I was aware of.

RG9998 = a surprise (to me) account that was listed under the one domain that I could not create a blog under.

I have 6 domains with Gandi, and I thought all were under RG9999. When I could not create a Gandi blog, I inspected the owner contact more carefully and discovered it was under the account RG9998. When I went to the domain control panel, one domain showed the owner as grayed out. Where it has the letters O A T B (owner, administrative, technical, billing), the "O" was gray, and that was where I found the odd account number RG9998. So, I log out of RG9999 and try to log into RG9998. No go. The password is bad. I do a password recovery which gets sent to my e-mail. At that point I can log into RG9998. I initiate an ownership transfer to RG9999. After it completes, all is well under RG9999, and I can create the blog.

So, where did the surprise account RG9998 come from? That's the question.

Guessing, RG9998 may have been created as a temporary or something when I transfered my very first domain to Gandi. I was never aware of it before this blog incident. After the ownership transfer to RG9999, RG9998 is now unused with no domains under it. It looks like I have two accounts and passwords to look after now. I'll investigate later how to drop the unused one.

I sent a support ticket to Gandi before I discovered all this. If they are perplexed, I'll point them here. Maybe it's all just a weird system quirk.

David, you are spot on in your observations!

New handles were made at Gandi:

• in 1996 when we changed from v1 to v2 of gandi.net's website. We created an owner handle from the original data that was given when the domain was registered (before that, domain's were only managed by the administrative, technical, and billing handles at Gandi)
• as a result of a transfer to Gandi (we created a new, temporary handle in the previous system that was based from the owner information provided by the previous registrar). Our new transfer system only does this for some extensions.

For deleting unused handles, consolidating, visit http://wiki.gandi.net/en/contacts