Macbook Pro Trackpad clicking but not working

See comment from rcha 101 in thread "Re: Trackpad clicks are not registering" where he suggests adjustment of the trackpad screws may solve this issue. Adjusting the trackpad screws also corrected my MacBookPro. Unfortunately this adjustment did not occur until after my Apple certified "Premium Service Provider" had replaced both the battery and trackpad at significant expense and no change in condition. I was told that both components had failed the Apple diagnostic test? Apparently post maintenance testing is not part of their repertoire. Lesson learned!

There are a large number of Threads on this issue. Many of the "solutions" appear to actually be work arounds. This suggestion by rcha 101 was the only positive fix (other than hardware failure and replacement) that I observed.

I have a similar issue with my 2008 15" MacBook Pro. Trackpad physical click has become unreliable over the last two months to the point where it no longer works at all. I had to attach a USB mouse to revise my Trackpad settings to enable "Tap to Click" to allow continued use of my laptop without dragging a mouse along. This is at best a work=around. Unlike John, I have used Parallels software since my machine was new to run in Windows mode (for remote login to the LAN at my workplace) not Bootcamp.

I had reviewed an earlier thread from late 2013 that had a number of suggestions. Of these two seem possible for my situation:

• the first was to thoroughly clean the trackpad including the crevices at the edges. While this has solved issues with erratic operation in the past following contact with greasy fingers, it did not solve the trackpad physical click not working issue for me.
• The second was that the battery swells as it reaches end of life and interferes with operation of the trackpad physical click. Given the age of my laptop, this may be plausible and I will consult the support personnel at my local Apple store to see if that is the case.

I discounted the following suggestions from the same thread:

• The issue was associated with operating system upgrades. I am using the original OSx 10.5.8. Now that I no longer need the Parallels software, I am planning to upgrade the OS but haven't done this yet.
• The issue could be resolved by shutting the lid, rebooting, reconfiguring system settings etc., Since the USB mouse works fine, the issue appears to be hardware related not software.

I will update this posting after seeking help from my local apple store. If there is a physical change to battery causing the problem, I am concerned this could lead to battery failure and consequential damage to my computer.