Unable to add the SharePoint farm and it fails with "None of the Web servers for the specified server farm could be accessed" if indexing locations are missing or corrupt.
Error in the selection list : None of the Web servers for the specified server farm could be accessed.
SPSWrapper log shows the following:
 01/09/13 15:20:14 IndexLoations is not null and Count is 2
 01/09/13 15:20:14 Sending index location C:\Program Files\Microsoft Office Servers\14.0\Data\Office Server\Applications\40606716-64f4-4dcd-aa48-5f08fbaa6212-query-0
 01/09/13 15:20:14 Sending index location \40606716-64f4-4dcd-aa48-5f08fbaa6212
 01/09/13 15:20:14 !! General Exception in Get Topology caught in GetTopology()
 01/09/13 15:20:14 General Information:
System.NullReferenceException: Object reference not set to an instance of an object.
1. This issue can occur if the indexing location is missing or corrupt.
2. It can also happen if the indexing location has been specified to an unused/unavailable destination.
The references to the Indexing locations specified in the SPSWrapper log need to be corrected in central administration console for the Sharepoint farm to be added.