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Installation Support FAQ

I installed a different version of Word (or) I installed a number of Office security patches and now I can't even start Aligned Elements anymore.

If the error claims "Unable to cast COM object of type 'Microsoft.Office.Interop.Word.ApplicationClass' to interface type 'Microsoft.Office.Interop.Word._Application'", do the following:

This is an error that can occur if a version of Word (say Word 2010) was installed and later a different (earlier) version of Word is installed (say Word 2007). The technical reason for the error has to do with the Word Primary Interop Assemblies that might have become mixed up.

This error is sometimes solved by uninstalling and reinstalling Word.

Another possible fix is to make the appropriate changes in the registry. In the log error message, there is a CLSID listed (like {00020970-0000-0000-C000-000000000046}). Open the registry editor (Run->Cmd->RegEdt32), copy the CSLID from the log-file (you can get help from Aligned to access the log files and extract the CLID), and perform a search in the HKEY_CLASSES_ROOT for the CLID.

You will find a key matching the CLSID. Expand this key and you should see 3 nodes: ProxyStubCLSID,ProxyStubCLSID32, and the important one - TypeLib. (Essentially what is happening is that when you make the COM call to a specific Office assembly. The assembly opens up the registry and finds this key which gives it the CLSID of the TypeLib it must call in order to initiate a call to the COM.)

The TypeLib key has two sub-entries of which one is a new CLSID. Copy that new CLSID. Now go to HKEY_CLASSES_ROOT->TypeLib and search for an entry matching the new CLSID.

Once you find it, expand it and see if there are multiple versions of the typelib i.e. 8.3, 8.4, 8.5. You want to eliminate the later versions that are pointing to non-existent TypeLib's.

To do this, expand the Version key (ie. 8.3), then expand the "0" key, then the win32 key, and check the value of the default entry. This value should be a file path or a reference to a Word PIA. If the entry is pointing to a Word version that is no longer installed, then simply delete this key, and now when the COM interface attempts to locate the latest TypeLib it will find one that does indeed exist, and will hopefully run error-free.