Recently while installing OBIEE on one of our training PCs, we ran into the following error.
Unable to connect
Specified driver could not be loaded due to system error 998 (Oracle in OraDb10g_home1)
This error occured at the time of setting up the ODBC connection. After some research the fix was to just change your enviornment PATH setting.
It seems that the OBIEE installation changed the PATH string by placing the new oralcebi home as the first path in the string. This annoyed its elder brother which already resided at the old oracle home and contained the 10g database. The ODBC dll (sqora32.dll) resides in the database home so it couldn’t find it when the path was changed by OBIEE installation. So the fix is to update the PATH string and place the Oracle database home as the first entry in the string.
As you see, the c:oracleproduct10.2.0db_1bin is now moved to the front, ahead of the f:oraclebi (this is where OBIEE is installed)