RN202 ReadyNAS 6.10.10: can't install apps?

You can downgrade to 6.10.9 (or 6.10.8) by manually downloading the arm zip

• https://kb.netgear.com/000065653/ReadyNAS-OS-Software-Version-6-10-9
• https://kb.netgear.com/000065170/ReadyNAS-OS-6-Software-Version-6-10-8

I suggest 6.10.9.

Extract the image file from the zip, and then manually install the image from system->settings->update in the web ui.  The install control will be on the left side of the screen.  The NAS will prompt you to reboot when finished.

But installs will likely still fail, due to the deprecation of Debian 8 last year.  There is workaround needed using ssh - see this discussion thread:

• https://community.netgear.com/t5/Using-your-ReadyNAS-in-Business/How-I-got-apt-update-and-install-to-work-with-Debian-Jessie/m-p/2309160

Post 1 and 37 are particularly relevant.

Note if you are ok with installing using ssh, you can stay on 6.10.10, and just apply the apt changes in the thread above.