I have identified the issue. The field is set to required when installing Composr CMS when it should never have been that way. It was probably like that for all of version 10, not just when I put in field validation. But the bug only recently showed up because required field validation didn't exist server-side until 10.0.45.

A resolution is going to be tricky because this involves deleting and re-creating the custom field (with required set to false) while migrating all of the member's values over to the newly-created field. As you mentioned your site has close to 100,000 members, I have to perform careful testing of the upgrade process (and simulate an upgrade on a site with 100,000 dummy members) before I make this fix available.

This is not an option my members have naturally chosen as I believe they are unaware of the benefits, so the numbers run to just a couple of dozen. If it makes it easier, I will note down those members that use this feature and re-entered their preference manually so that the field can be recreated without content.

That would make it easier, but I must think of the broader implications. Your situation might not be true for other people who would also have the same bug. Therefore, I still have to proceed with the migration route.

Automated response: Smart topic notifications CPF was required when it should not be

Smart topic notifications CPF was required when it should not be. This patch fixes the CPF by editing it so it is not required, and thus won't trigger the server-side field validation.

This is a substantial fix! Take great care when applying it. Read all directions below carefully:

1. MAKE A BACKUP of your website and TEST THE BACKUP to make sure it works.

2. Extract the files from this archive into your Composr installation; replace files when prompted.

3. Log in to your site as an admin.

4. Go to the Admin Zone > Structure > Addons > Module management

5. Select Admin Zone

6. Scroll down to admin_version. It should say that it requires an upgrade.

7. Click the action button to upgrade the module.

8. You should get a successful message within a few seconds.

NOTE: This bug fix was only tested on the Conversr forum driver. It might not work with other unsupported drivers.

TQ please report to me when you can if the above hotfix fixes the bug. Thank you.

I went a different approach to fixing the issue which is much more memory / resource friendly and did not require migrating field data. On a test site with 100,000 members, it only took about 2-3 seconds for the module to upgrade.