Error Type: Microsoft OLE DB Provider for Oracle (0x80004005)

I am currently in the process of a web server migration. There are some applications which are giving me some trouble. I have migrated some web applications, but an error msg appeared in IE informing me that the Oracle Client was needed. I then proceeded to install the Oracle 9i Client.

However, after installing the Oracle Client, I was instead presented with another different error as below (same error for all applications):
-------------------------------------------------------------------
HTTP 500.100 - Internal Server Error - ASP error
Internet Information Services

Error Type:
Microsoft OLE DB Provider for Oracle (0x80004005)
Oracle error occurred, but error message could not be retrieved from Oracle.
-------------------------------------------------------------------

All these applications could run on the old web server without this problem. Below are the web server specs (only the relevant ones):

New web server: Win2k SP3, Oracle 9i Client

Old web server: Win2k SP2, Oracle 8i Client

I have confirmed with the application developers, they have stated that there is no need to specify a DSN as there is already a connection string in their coding.

I have gone through the MS Knowledge Base, but found nothing that could solve this problem.

Can anybody please help me with this problem here? Thanks!