@ Scott
Re: "All else fails, format that computer. That will fix everything. "

lol, but a tad nasty! I think it is safe to say that not everyone who reads that bit of advice will grasp the implications.

I think this is the same problem that I'm having. I was able to get the html editor back up by manually uninstalling then running CCleaner. I'm now still trying to get Sonar running as it's doing the same. I'm trying to get everything in order to do a refresh of windows.

I'm on a laptop which doesn't have ccleaner (instead something else), so I can't check if something happens with Sonar. But I will check it next week when I'm home with my desktop computer (which has ccleaner). Also, I don't remember the exact settings available, if it is for all CC software or just for the Editor. I've never had problems with Defender blocking things - on either computer.

I checked Coffee.exe and Sonar.exe with the virustotal website . It failed to find any antivirus programs (it checked over 50) that had any problem with them. It seems therefore unlikely that antivirus programs are causing the disappearances mentioned.

My reason for checking as above was that I had the problem of a well-respected non-CoffeeCup program disappearing. The CEO of the software company checked using virustotal, and was able thus
(a) to identify the antivirus program causing the problem, and
(b) to liaise with the antivirus company to get the false-positive finding and quarantining remedied.

If cleanup programs and malware prove not to be the cause of the problem, and if a solid-state drive is being used, it could be failing. I had an early model fail, causing various troubles in Windows, and it took me ages to find the real culprit. If a traditional rotating hard drive is being used, it might be worth checking for bad sectors or cross-linked files.

Frank

I've been having this happen again. This time it happens when I try to ftp a file to the host with the html editor. It looks done and I switch back to the local tab and then when I switch back to the server tab I get a error 143 completing current task. It won't stop popping this error when I switch tabs so I close the editor and relaunch. It opens and loads the last pages open and then promptly closes. When I relaunch it can't find the coffee.exe file. This last time I made a copy of the exe file and when I changed it's name to coffee.exe it disappeared or was promptly deleted as in I saw it happen. Very strange behavior.

If not already done, I would be inclined to use the system file checker as shown here, in case some fault has crept into Windows 10.

Frank

Have you heard about anyone else who has the same problem, Eric? If it is only you, it must be something with your system. Frank's suggestion is a good one.
BTW, have you got a second machine where you could try it on?

I tired putting exceptions in Windows defender and it still does it. I'm scanning now to see if there's anything going on. I think I did that last time It got this bad but ended up doing a refresh.

Scan found nothing. I'll probably do a refresh of windows again as that would be the quickest to get me back up and running. I have this project pressing and I need to get a testable version running in a week.

I might be way off, but when installing, are you right mouse clicking over the install file and installing as administrator? Might have something to do with it, especially in Windows 10. I run Windows 10 and ccleaner and have all the CC software, but thankfully not having these issues.