Thomas, thanks for you help. I did make a change in my listener.ora file to include cassure as the SID (see below). When I run
lsnrctl status
I get the following error msg:
TNS-12560 TNSrotocol adpater error
TNS-00530 protocol adpater error
32-bit windows error: 2 no such file or directory

I also found on another message board this advice and applied it to my pc (to no avail):

Try setting the TNS_ADMIN entry in your windows registry and give appropriate value.
To add this entry perform the following actions.
Click on Start -> Run then press Enter the type regedit.
Add the TNS_ADMIN environment variable to the HKEY_LOCAL_MACHINE\Software\Oracle\Home key by right mouse clicking, then selecting New -> Key -> String Value.
I think your network files are on
E:\oracle\product\10.1.0\db_1\network\admin
(Verify if thats the correct path of your listener.ora, sqlnet.ora etc) and assign the above mentioned path as value for TNS_ADMIN in registry.
Then open a command prompt and type this
E:\oracle\product\10.1.0\db_1\bin\lsnrctl start (press enter)