In addition to the programs I usually use, I've now run Malwarebytes' Anti-Malware....
The 'Quick Scan' (It took 4 minutes), found 4 'objects'. - Their removal had no effect.
The 'Full Scan' of my OS drive, revealed nothing, - (And took 20 minutes!)
The 'Full Scan' of my other drives took a total of 44 mins, and found nothing.
I then downloaded and ran SUPERAntiSpyware.... The 'Quick Scan' took 24 minutes and revealed 104 Adware Tracking Cookies. - Their removal made no difference!
- But the program looks interesting and may be worth keeping, - thanks!
So I'm still stuck with having to run MA2.6 every time after running MA3Beta7, - if I want to then run DA.