Field Exception: Attempt to create a field of unknown type group_email

I can confirm this happened to me several times in previous versions. Was never able to properly diagnose or debug it, in same cases it worked and in others it didn't. :'(

Are you using the right version of Organic Groups? OGM only works with the 2.x series of Organic Groups. I remember seeing the same error when I accidentally installed the module with OG 1.4.

Could you verify you're using the right version of OG? Also, Mahfiaz is this documented in the INSTALL.txt that people need to use OG 2.x?

Thanks Kyle for suggestion. I updated INSTALL.txt file and also added required version 2.x to og_mailinglist.info

tommyvyo, if you use og-2.0-beta1 and this error still shows, then please speak up. Thanks for reporting.

I have seen this error myself, but it was at least a month ago or so.

This most likely is caused by og or og_mailinglist code not being correctly indexed or loaded. If this is true, then doing "Cache clean" should be sufficient.

We could workaround this by including needed files manually, but I am not yet convinced this is really neccessary.

Pretty sure it was og-2-beta1 not being installed.

Haven't seen it since.

tommyvyo, so it was result of using an older og release? (Sorry, cannot be sure when reading your sentence.)

I added a requirement of og >= 2.x to .install file the other day, so it will not be possible to enable it with previous releases.

Tried fixing migration issue from other thread and did so by uninstalling OG Mailinglist and OG. Reinstalled both with proper requirements and I'm still getting this error.

Any advice or suggestions on how to proceed?

If you can, the simplest thing is to just start over from a fresh install of Drupal.

If you cannot start over, you could send me your database dump. Otherwise I cannot really help here, I don't get this error.

Solved this error:

Cannot modify header information - headers already sent by (output started at /usr/share/php/drush/includes/output.inc:37) bootstrap.inc:1239               [warning]
FieldException: Attempt to create a field of unknown type <em class="placeholder">group_email</em>. in field_create_field() (line 110 of /home/thomas/code/ania-d7/modules/field/field.crud.inc).

By adding field_info_cache_clear(); to line 3 of og_mailinglist.install.

Will report back tomorrow on any other issues we may come across.

Last week I tested it and was able to get this error (don't know how exactly, happened only once). Adding field_info_cache_clear() made it worse, so it ended with fatal error. I hope I am able to reproduce it once more. But I still don't know what causes it.

I was able to reproduce this. I think this is caused because field definitions are cached. So when og_create_field is called, the cached is not yet updated, so the installer can't see the field yet. I have a patch attached that I think should fix it, and not cause any more errors. I just forces the cache to be rebuilt.

Thanks, schultetwin, this one was bugging me for long time. Fix is committed now.