Activation /authorisation problems please help distraught daughter

Question

I hope someone can help me.
I bought my daughter a Sony Touch ereader for her birthday because she was envious of mine which I have had for a year and love.  I had to go to work on her birthday so she was on her own when she set it up and I'm not entirely sure what she has done.  As far as I can make out she installed Adobe Digital Editions about a month ago knowing that she was going to get an ereader and downloaded some ebooks to start with thinking she could transfer them to the ereader when she got it.  I think she got herself an Adobe ID at the time but as far as ADE goes I suspect she did not authorise her computer with that ID at the time.
When she installed her ereader, ADE prompted her to authorise her computer which she did using the Adobe ID.  She also bought some more ebooks which she transferred to her ereader no problem. However she still couldn't open any of the ebooks she bought before authorising.  She has only ever used the one laptop for all of this so the issue with two separate accounts on two different computers should not apply.
I had a look at all the troubleshooting sites I could find and it suggested deauthorising and reauthorising the computer.  That's when it all went pearshaped.  She now can't open ANY of the purchased ebooks even the ones she could open previously.  The ereader properties said it was authorised for Adobe DRM content and it had the right Adobe ID address.  But when she tries to open them it says she is not authorised to preview the book.  I have checked she used the same adobe ID and password for everything so it's not that
One of the things one always tries is uninstalling and reinstalling problem software.  So I tried reinstalling ADE to make sure we had the most up to date version. But then it didn't recognise the ereader.  WHSmith ebooks customer support said to download ADE yet again. I have now hit the too many activations problem.  She has submitted a case through the web based support portal case number #0181349188 to get her permitted number of activations reset because we can't do anything until that is sorted out.
However I don't think that will solve the problem because as far as I could tell the computer was authorised properly but it would not recognise the ebooks downloaded before it was deauthorised and reauthorised.  I don't know why it's an issue because it's not as if she has tried to transfer content from or to different computers or devices, she only has the one laptop.
Please can anyone help me sort this out.  She is absolutely distraught as she has spent all her birthday money on ebooks she can't now open and as she is a student she can't just afford to write off the loss. And I feel sick about it because I thought she'd be thrilled with her new toy
I'm reasonably computer literate and I have never had any problem with my own Sony ereader (but then I tend to read the ...manual).  I use my own ereader with a different computer by the way so I don't think it's a conflict. But I am stumped by this.  Her laptop is about a year old a Sony Vaio running Vista Home edition.  The registry may be a bit cluttered but although I can reinstall Windows if I have to I have never attempted a registry edit

Answer 1

I am a very happy woman!! (And I have a very happy daughter)
Thank you so much for your help.  I still don't know what she did but it seems to be fixed
I  got an error message when I connected the ereader saying a problem occurred while installing the Ereader software on your computer and I still couldn't open some of the ebooks even though I could open them in ADE so my heart sank.  However I deleted the problem titles from the ereader and reimported them  and then they were fine. I don't know what the error in installing the software was as it seems to be fully functional albeit rather slow to import large titles
She has been given strict instructions not to muck around with anything
Happy Christmas!!