Error when importing from Redmine

[Leonard Pooch]

Hi, I'v already import all of my projects in Jira via CSV and it worked well but now I need to recover all files attachments from Redmine and I read that I could do that directly via the Redmine tab in the Import Wizard.

After mapping all of my fields and other stuffs, I launched the import and got the following error, with a bunch of html between those infos.

2019-08-28 11:54:15,836 ERROR - Irrecoverable error while importing data from redmine
com.taskadapter.redmineapi.RedmineFormatException: Bad categories response

at com.taskadapter.redmineapi.internal.Transport.getChildEntries(Transport.java:492)
	at com.taskadapter.redmineapi.ProjectManager.getVersions(ProjectManager.java:181)
	at com.atlassian.jira.plugins.importer.redmine.manager.CachedJiraRedmineManager.getVersions(CachedJiraRedmineManager.java:181)
	at com.atlassian.jira.plugins.importer.redmine.RedmineClient$4.getValue(RedmineClient.java:146)
	at com.atlassian.jira.plugins.importer.redmine.RedmineClient$4.getValue(RedmineClient.java:143)
	at com.atlassian.jira.plugins.importer.redmine.RedmineClient$ValueAccessor.get(RedmineClient.java:465)
	... 35 more
Caused by: org.json.JSONException: A JSONObject text must begin with '{' at character 1
	at org.json.JSONTokener.syntaxError(JSONTokener.java:410)
	at org.json.JSONObject.<init>(JSONObject.java:179)
	at org.json.JSONObject.<init>(JSONObject.java:402)
	at com.taskadapter.redmineapi.internal.RedmineJSONParser.getResponse(RedmineJSONParser.java:716)
	at com.taskadapter.redmineapi.internal.Transport.getChildEntries(Transport.java:488)
	... 40 more

I'm using Jira 8.3.0 and Redmine 3.3.1.

Can anyone please tell me how to fix that or at least explain to me an other solution to import my attachments even if it involve touching to the database.

Thanks,

Leonard