We have been struggling with a problem that on the surface seemed absurbly simple. We created a contact us module designed  to submit an email to an admin user with some comments from the submitter. Simple enough.

The module worked perfectly if the user was authenticated. It didn't make any difference what the user's permissions were just as long as they had logged in. However, once the user logged out the module would still display correctly but all the actions (submit button in our case) did not respond. The page would refresh but the event would not fire.

After about 8 hours of trying every DNN permission under the sun we started comparing our module to the survey module. Everything was comparable expcept for one setting - the module cache time and the corresponding default cache time (which provides the default value when the module is created). Our cache time was 60 (the default) and the survey module was 0. After changing our value to 0 the problem went away.

IMHO this is a DNN bug. If a user clicks a button requiring custom code to execute then DNN should not be serving up a cached page. At the very least the defaukt cache setting should be set to 0. I also do not understand why a cache time needs to be specified  at the module level when there are already cache settings under the host settings.

For the record, this problem was encountered on DNN 4.5.3, running on a dual core 4GB server. Caching is set to moderate (disk based).

I am glad that you were able to get your issue resolved, however, I will disageee and say that this is NOT a bug in DNN.

Each module can have its own cache time defaults and you can specify your desired value in the .DNN file for your module.  By allowing the specification of cache time it allows the developer to determine the appropriate time to store the content before rendering.  Yes, this does break any module that has interactions with the user, that is why in the module development guides they mention setting this to zero.

Even with caching turned on at the site level you must have the module specific setting as you do not want all modules cached, and that is the only way to do it.  IMHO.