Files are missing from Gatling html report

In my test I would like to be able to see statistics for each virtual user separately, so my scenario looks like this:


val scn: ScenarioBuilder = scenario("My scenario")
  .feed(credentials) //contains username, password etc.
  .group("User ${username}") {
 //some actions here, some of them also grouped


When the report is generated, I see a group for each user as expected on the main page.
But when I click some group, the file is not found: Firefox can’t find the file at /group_someusername-4821f.html. Checked the folder with html report, and there is actually no such file.
If I expand topmost group on the report main page further and click some of its subgroups, subgroup details pages are opened as expected.

Does anybody know the reason for this and how can I avoid it?
I’ve never encountered such a problem with my other scenarios, but they all were rather grouped by request types than usernames.

Gatling version 2.3.0

Please provide your simulation.log.

Note: Gatling reports are really not intended to deal with thousands of group/request types.So using the userId or the url in group/request names is usually a very bad idea.