During the test of a BSP application from tr sicf you can get this error message:
Das Objekt default.htm in der URL /sap/bc/bsp/sap/.../default.htm ist nicht gültig.
Object default.htm is not valid in URL /sap/bc/bsp/sap/.../default.htm
(default.htm is just an example page in this case)
The main reason behind it that many BSP applications do not work by means of "Service to test" in the SICF,
because they do not have any initial page.
This is application specific -> the default.htm is called,which does not exist in the mentioned application.
You can call the applications in transaction SE80 by selecting one of the files from the flow logic.
For more information please check the following SAP Note:
1944001 - BSP Exception: Das Objekt ... ist nicht gültig / Object ... is not valid