Toad Data Point 5.5 -- keep getting error, "Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index" whenever navigating to the Script tab in Explorer. Connecting to a SQL Server database using native SQL Server connection (not ODBC). Any help would be appreciated!
Welcome back to the TDP forum.
Acknowledged, and documented. This is an issue that was discovered in 5.4 just before 5.5 came out. Should be fixed in the next release 5.6, fingers crossed. 
Great, thanks for the quick reply!