Editing registry for the error - One of your object libraries (I) is missing or damaged. Please run setup to install it

Question

When I opened an excel (.XLS) file today, I got an error - One of your object libraries (I) is missing or damaged. Please run setup to install it. I don't know why that happened, but it could be because of the following reasons -

1. Windows update a few minutes ago.

2. Installing a component by running this in cmd - C:\Downloads\AccessDatabaseEngine_x64.exe /passive

I found a solution which suggests registry edits. I am not confident of it, but I tried it anyway - http://answers.microsoft.com/en-us/office/forum/office_2010-excel/one-of-your-object-libraries-i-is-missing-or/cf3e3acc-ad69-e011-8dfc-68b599b31bf5

Your problem can be resolved without any re-imaging. The procedure is as follows:

1 - From "Programs and Features" select Office 2010 and click "Change".

2 - Make Excel unavailable.

3 - Start the registry editor and remove any references to Excel underneath:

Registry entries -

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\8.0\Excel
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\9.0\Excel
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\10.0\Excel
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\11.0\Excel
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\12.0\Excel
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\14.0\Excel

4 - Browse through the HKEY_USERS tree and remove all references to Excel underneath:

HKEY_USER\<guid>\SOFTWARE\Microsoft\Office\8.0\Excel
HKEY_USER\<guid>\SOFTWARE\Microsoft\Office\9.0\Excel
HKEY_USER\<guid>\SOFTWARE\Microsoft\Office\10.0\Excel
HKEY_USER\<guid>\SOFTWARE\Microsoft\Office\11.0\Excel
HKEY_USER\<guid>\SOFTWARE\Microsoft\Office\12.0\Excel
HKEY_USER\<guid>\SOFTWARE\Microsoft\Office\14.0\Excel

5 - Change the Office 2010 installation again, adding Excel.

My questions are -

1. For step 3, I see only 12.0 and 14.0 listed. There is no entry for Excel at all. But, there is an entry for Word and Access under 14.0.

2. In step 4, I see weird looking numbers in place of GUID. There are no entries for Excel or office in all but one of them.

How do I fix this mess ?