Hi,
The well-known IE dowload bug (or feature) began to trouble the Lesson module in Moodle version 1.5. As you might well know, IE puts the files to be opened by an external application to the cache directory. If caching has been prevented with headers, the external application cannot open the file.
From '/file.php' (not in '/mod/lesson'):
---line 83---
$lifetime = 0; // do not cache assignments, students may reupload them
---
This line prevents caching of files posted as assignments, and also makes it very hard to download the files for grading.
I fixed this by setting the value to 10 (seconds). It might even be a smaller value. I do not think that the comment (do not cache...) applies to short life times, does it?
