I have moodle installed for 2200 students has about 6 months, without problems.
Since last week that I have a problem with the generator of random questions. Always that I try to generate a test gives an error to me of the type: the number of random questions is superior to the number of questions of the category. However such is not truth. The problem happens, in average, during 3 hours and later it passes. Hours later return to occur.
Other strange errors have happened since last week: fóruns that they leave of being generated: could not find fórum, or when I enter in the platform does not have visiveis courses, I have to make f5. In a situation complained of invalid id context...
the problem started to occur after having extinguished a test attempt, that i had been, as i was a student.