BleepingComputer.com: A problem with Mozilla Thunderbird

Hi Everyone this is rreally bugging me !!!
My OS is Windows XP SP 3 and I use Mozilla Firefox as a web browser and Mozilla Thunderbird as my email client. When i receive an email with an attachment in PDF format I am unable to open it while in Thunderbird. When I try to open the attachment a dialogue box appears asking if I want to "Open with Acrobat 9 [Default]" or "Save to Disk". If I click on the "Open with Adobe Reader 9 [Default]" option then Office 2007 opens and a File Conversion box appears asking that I select the encoding that makes the document readable. The options are Windows [Default], M S DOS or Other. No matter which of these options is selected the document does not open in anything that is readable [to me anyway].
If I click on the "Save to Disc" option [rather than Open with Acrobat 9] when trying to open the attachment I can save the document to my Desktop then open the document from there using Adobe Reader 9.
I don't know why I have to save the attachment to my desktop in order to open it but I would really appreciate any advice as to how I can open these type of attacments while still in Thunderbird.
Thanks
NONIC

Try this:

Double click on My Computer & go to Tools > Folder Options, click on the File Types tab, scroll down until you find PDF then click on it once to highlight it & check in Details right below it to see what it's set to open with. Click the Change button & select Acrobat from the list & make sure there's a checkmark next to Always Use selected program. If Adobe is selcted you could try going to the Thunderbird Forums & submit a bug & see if they can help.

Thank you for your response and advice. I have followed your instructions and am very pleased to report that the problem has been resolved, It is now so much easier to open PDF documents received as attachments. I really appreciate your help in resolving this issue and am very grateful for your time and interest.
NONIC