@Mych 

This app wasn't shown to me as one that would be impacted.

@ember1205 

same to me - I downloaded the App and installed it without a Message or warning that the App is not 64 bit!

@ember1205 It didn't for me but I assumed that that was because I had auto update turned on. I have managed to uninstall it though. I had to do it via Finder... go to apps, find the app and then just bin it. The new version of Mac OS has caught out a whole bunch of people acording to the blogs I've been reading. Even some versions of high end applications like photoshop have stopped working

@Kevin_Z When I checked the list of 32 bit apps that were on my iMac (I used System Report) before I updated to OS Catalina 10.15 TP-Link was not listed as a 32 bit app so I assumed it would work. Now that I have updated to Catalina I get the same results as everyone elso who has reported the problem, the App opens and then as soon as I authorise it the app just closes and that's it, here is the screenshot before I enter the required  password

@Adrian991 I assumed it was 32bit as this has been the general reasons for apps to stop working but I may be wrong. The only other thing I can think of is that it required admin rights and even though we are providing permission via our password Mac OS Catalina is locked down even more. Looks like the tp-Link developers need to sort this out prety sharpish. Luckily I've been able to load the app on my laptop which hasn't been upgraded yet.

HI @Kevin_Z , add me to the growing list of affected users.  Disappointed that this slipped the attention of app support.......

Exactly the utility is 32bit, Mojave doesn't allow anymore for 32bit apps, please update it!

Another user harmed by this...

Any E.T.A on providing the x64 bits? There's lot of issues with the firmware I'm currently using, and for me an upgrade is quite imperative.

Thanks in advance.

@rooob FYI: tpPLC was not 32bit and nor was it Mojave... It was a 64bit app as listed in System Info and it is Catalina that has closed the door on 32bit.