Quicktime Version 10.5 (1015.2.1 on Version 10.15.7 Catalina can't access camera

Thanks for consideration. I had tried with 'csrutil enable' and with 'csrutil disable'. No difference. I did manage to make it work finally. I'd done the following.

1) execute 'codesign -d --entitlements - /System/Applications/QuickTime\ Player.app' to see what privileges are needed.

They are:

<key>com.apple.application-identifier</key>

<string>com.apple.QuickTimePlayerX</string>

...

<key>com.apple.private.tcc.allow-prompting</key>

<array>

<string>kTCCServiceMicrophone</string>

<string>kTCCServiceCamera</string>

<string>kTCCServiceScreenCapture</string>

</array>

Then, with 'csrutil disable', can do the following :

2) 'launchctl unload -w /System/Library/LaunchAgents/com.apple.tccd.plist' to disable to tcc service

and then add entries with :

3) 'sudo sqlite3 ~/Library/Application\ Support/com.apple.TCC/TCC.db "insert into access VALUES('kTCCServiceCamera','com.apple.QuickTimePlayerX',0,1,1,NULL,NULL,NULL,'UNUSED',NULL,0,1541440109) ;" '

and iterate the line above for each privilege needed.

And re-enable tcc service with :

4) 'launchctl load -w /System/Library/LaunchAgents/com.apple.tccd.plist'

After that, I could see quicktime in the security and preferences list and could check it. The app just wouldn't prompt for access, I dunno what service is needed for that but I just got fed up and did the above so I could move forward.

Also 10.15 does not seem to have tccctl program ... I could not find it, that would have likely been easier than the above.

Can close ticket, thanks again.