I've had a similar issue with Outlook 2007 on a Vista Home Premium Acer. Although I do not have to try to send an attachement to have the problem. Usually I can send one or two Emails before Outlook locks up and keeps running through the tasks, trying to send the Email. I can stop it one of two ways; task manager or keep hitting cancel until it allows me to close Outlook. When I restart Outllok the email is still in the outbox and when it tries to resend it it locks up again. I have to delete the Email to get it working for one or two Emails then I'm back to the same problem.
At first I thought it was the email address I was using. I have about 6 Emails I use (3 for my business and 3 or so for personal). I deleted each one and ran them one at a time and I have the same issue on each one. Which tells me the issue is with Outlook not the addresses.
I opened a ticket with Microsoft on January 21, 2008

. Below are the steps they gave me to try and resolve this problem. The top message is the latest step they have given me. One thing I will say is as time goes on and the problem does not resolve the less interested they seem to be. I haven't tried the solution listed above but I am going to try it before I start deleting anything from the Registry.
One solution I found was to remove the software from Logitech that was for a wireless mouse and keyboard. The software is not compatable with Vista but still installed. But this did not work either.
After almost a month trying to resolve this I am starting to feel as though the $100 I spent for Outlook 2007 was a rip off.

If anyone comes up with a solution that works please post it!
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Delete Profile Registry:
1. Click Start, click Run, type regedit, and then click OK.
2. Navigate to the following registry key:
HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows Messaging Subsystem\Profiles
3. On the File menu, click Export.
4. Specify a file name and location where you want to save the exported registry file, and then click Save.
5. Right click on the profiles, and then click Delete.
6. Quit the Registry Editor.
7. Re-configure your account again and test the issue.
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Based on my research, the issue may be caused by that some files of Office 2007 have been corrupted. I believe the best and the most efficient method is to reinstall the Office 2007. We can run the Microsoft Windows Installer Cleanup utility to remove the Windows Installer registry settings, and then reinstall Office. To do this, follow these steps:
Note: Since some anti-virus programs will cause unexpected application conflicts, please temporarily disable or remove any anti-virus, Firewall, or anti-spam programs on your computer before we go any further.
Remove and reinstall Office 2007 with the installation disk
Before we start any items in these steps, let’s back up your outlook data so as to avoid further file loss. For more information on back up your outlook data please go to the following link:
For Outlook 2002 and Outlook 2003:
Q287070 OL2002: How to Back Up, Restore, or Move Outlook Data
How to manage .pst files in Outlook 2007, in Outlook 2003, and in Outlook 2002
Note: this article also applies to Outlook 2007.
Note: If you don't use Outlook for your emails, just skip this step and move on.
1. Download and install the Windows Installer Cleanup Utility.
http://download.microsoft.com/download/E/9/D/E9D80355-7AB4-45B8-80E8-983A48D5E1BD/msicuu2.exe
2. After you install the Windows Installer CleanUp Utility, click Start menu-> All Programs-> Windows Install Clean Up.
3. Highlight All Microsoft Office entries in the list and then click Remove. Quit the Utility.
Note: If you have got any other old or redundant office entries such as Office 2000/XP/2003/2007 or other Office stand alone products such as Visio, OneNote, Project, etc in the list, please remove them together.
4. Close all applications.
5. Click Start menu-> Run, type "regedit" (without the quotation marks) in the Open box and press Enter.
6. Expand the registry tree on the left pane and locate the following two registry keys:
HKEY_CURRENT_USER\Software\Microsoft\Office
HKEY_LOCAL_MACHINE\Software\Microsoft\Office
7. Right-click on this key and click Delete to delete those keys.
8. Open Windows Explorer, and then browse to the "C:\Program Files" folder
If it exists, rename the "Microsoft Office" to "Microsoft Office OLD"
If it exists, rename "OfficeUpdate" to "OfficeUpdateOLD"
If it exists, rename "OfficeUpdate11" to "OfficeUpdate11 OLD"
If it exists, rename "OfficeUpdate12" to "OfficeUpdate12 OLD"
9. Click Start menu-> Run, type "%Temp%" (without the quotation marks) in the Open box and press Enter.
10. Empty the %Temp% folder.
Note: If some files can't be deleted, please skip them, which don’t influence the result of the troubleshooting.
11. Empty the Recycle Bin.
12. Restart your computer and install Office 2007.
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if create a new profile fix the problem, there is no need for you to reinstall Outlook. Meanwhile, I want to explain that Outlook puts all the data in Personal Folder File (.PST) such as e-mails, contact information, etc. Let's try to find your original Person Folder File. I would like to explain that all PST files are located in the some hidden folders by default.
Step 1: Find original data
1. Click start -> Search.
2. Click Advanced Search.
3. Make sure "Include non-indexed, hidden and system files" are checked:
4. In the "Name" box, type "*.PST" (without quotation marks)
5. Click "Search".
Note: The .PST files are always located in the C:\Users\<user account>\AppData\Local\Microsoft\Outlook\.
(<user account> is the name of your windows account, C: is the system partition where the Operation System locate.)
Can you reach any PST files then?
Meanwhile, I have also included the following Microsoft Knowledge Base article for your reference:
Q287070 OL2002: How to Back Up, Restore, or Move Outlook Data
How to manage .pst files in Outlook 2007, in Outlook 2003, and in Outlook 2002
Note: this article also applies to Outlook 2007.
Step 2: Import PST file via Outlook 2007 with new profile
1. Start Outlook 2007, and then click File -> Import and Export.
2. Select Import from another program or file, and then click Next.
3. Select Personal Folder File (.pst), and then click Next.
4. Locate that temp folder, select one PST file, select Replace duplicates with items imported, and click Next.
5. Check Include subfolders, and then click Finish.
6. Repeat steps 1, 2, 3, 4, 5, until all the PST files are imported
Note: If you cannot impost these PST files, I suggest you directly open them via Outlook. To do this, you can: Start Outlook 2007->click File->Open->Outlook Data File and locate the PST files to open them.
By the way, you can delete your old profile by Click Windows icon-> Control Panel-> click the Mail icon->In the Mail Setup dialog box, click the Show Profiles button and highlight the profile to remove.
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At this stage, I recommend you try the following steps and see whether it helps. Thanks for your time and efforts.
Note: Since some anti-virus programs will cause unexpected application conflicts, please temporarily disable or remove any anti-virus, Firewall, or anti-spam programs on your computer before we go any further.
Step 1: Create a new profile
A new profile is a new environment for us to use Outlook. To create a new profile is only for a test to see if the problem is related to the corrupt profile of Outlook. Creating new profile will not do any damage to the old profile and won't cause any data loss..
1. Click Windows icon-> Control Panel.
2. Click Switch to Classic View, and then click the Mail icon.
3. In the Mail Setup dialog box, click the Show Profiles button.
4. On the General tab, click to select the Prompt for a profile to be used check box.
5. Click Add.
6. In the Profile Name box, type a descriptive name for the new profile, and then click OK.
7. In the E-mail Accounts dialog box, click Add a new e-mail account, and then Click Next.
8. Select the appropriate server type for your e-mail account, and then Click Next.
9. Fill in the appropriate information as prompted, and then Click Next and Finish as needed.
10. Click OK.
11. Restart Outlook and select the new profile in the popup window.
If you need more information, please follow the article below:
Q829918 How to create a new e-mail profile in Outlook 2007
How to create a new e-mail profile in Outlook 2007 and in Outlook 2003
Is the problem resolved now? Check the issue again and please DO NOT import the original data at this time.
We can import the original data to the new profile. Please refer to the following article:
Q287070 OL2002: How to Back Up, Restore, or Move Outlook Data
How to manage .pst files in Outlook 2007, in Outlook 2003, and in Outlook 2002
Note: this article also applies to Outlook 2007.
If the problem still persists, please move to the Step 2
Step 2: Download and install the latest Outlook Connector with test acccount
Please download the Outlook Connector from the following link and install it.
Microsoft Office Outlook Connector
http://www.microsoftcom/downloads/d...6a-931e-438a-950c-5e9ea66322d4&DisplayLang=en
After you install the Outlook Connector, we can configure the test account in it. To do this, you can:
1. Start Outlook 2007.
2. Click Outlook Connector->Add a New Account.
3. Configure the test account in the box.
Does the test account works well in Outlook Connector now? If so, please repeat above steps to configure your own MSN/Hotmail account in Outlook Connector. Please let me know the test results.
If the test account works well in Outlook Connector, this issue is most likely related to the MSN/Hotmail account. I recommend you directly contact our MSN support by phone:
MSN Technical Support Center at (866) 672-4551 (United States only). Representatives are available from 5:00 A.M. until 10:00 P.M. Pacific Time, Monday through Friday; and 5:00 A.M. until 5:00 P.M. Pacific Time, Saturday and Sunday.
In addition, if you need the Chat support or Email support, you can go to the following web site:
http://support.msn.com
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