Yes the D: drive was NTFS formatted. I found that the Apache service had not started because port 80 was being used by IIS. I altered the httpd.conf file to show port 81 as the one listened to - then started the Apache service, went to [
localhost]) and found that, after a few seconds, it worked. I the meantime, I unnstalled WAMP, re-installed as "administrator" - just in case. All is now good - thank you.