"App Store cannot be opened because of a problem." Check with the developer to make sure App Store works with this version of macOS. !! I have Catalina for months now and used App Store several times.
How do you update the App Store app ?
iMac 27", macOS 10.15
The only app I recently installed is CleanMyMac.
It makes me suspicious. Is this trustworthy ?
No. Do not use it. Uninstall it in strict accordance with its instructions immediately.
Ill-conceived non-Apple "cleaning" products are scams that generally require erasing the affected Mac and rebuilding it from the ground up.
Is MacOS known to generate a message ".. plugin will damage your computer.. REPORT MALWARE to Apple.." or which software does ?
Yes.
If that message continues to appear you will need more assistance. Fraudulent "Adobe Flash" installers are a common vector for malware intrusion: Beware bogus Adobe Flash "installers" - Apple Community.
The only app I recently installed is CleanMyMac.
It makes me suspicious. Is this trustworthy ?
No. Do not use it. Uninstall it in strict accordance with its instructions immediately.
Ill-conceived non-Apple "cleaning" products are scams that generally require erasing the affected Mac and rebuilding it from the ground up.
Is MacOS known to generate a message ".. plugin will damage your computer.. REPORT MALWARE to Apple.." or which software does ?
Yes.
If that message continues to appear you will need more assistance. Fraudulent "Adobe Flash" installers are a common vector for malware intrusion: Beware bogus Adobe Flash "installers" - Apple Community.
The App Store is updated along with macOS, so be sure to keep macOS updated.
Otherwise read If you can't connect to the App Store, iTunes Store, or other Apple services.
Still having trouble? Use macOS Recovery to reinstall macOS.
Thank You. The problem disappeared.
"resolved" would be the wrong wording...
Clean & healthy iMac for 5 years and now suddenly a big scare.
The diagnostics showed that an -old never used- 32bit Adobe Premiere software interfered with the App Store app.
Then this malware report showed up.
I binned the plugin and the Adobe software.
Any thrusted anti-virus software for MacOs ?
Then this malware report showed up.
That was not a malware report.
Any thrusted anti-virus software for MacOs ?
There are no macOS viruses, nor will there be any macOS viruses, ever. Install nothing of the sort.
The problem was outdated or poorly written software which you properly disposed of.
Thank You. this reassures me in general.
But the automatic error report to Apple clearly indicated that a dormant 32bit Adobe software that I never opened nor touched, suddenly screwed up the important Apple Store app. I do not understand how an executable that was not invoked, suddenly messes with an other app.
Is MacOS known to generate a message ".. plugin will damage your computer.. REPORT MALWARE to Apple.." or which software does ?
The only app I recently installed is CleanMyMac.
It makes me suspicious. Is this trustworthy ?
Very helpful. Thanks a lot !
App store cannot be opened
