Roots of the issue
If profiles fail during inviting with such errors:
Incorrect connect response (5xx)
LinkedIn error. Incorrect connect response (4xx)
LinkedIn error. Incorrect invitations response (5xx)
LinkedIn error. Incorrect invitations response status code
Then you should know that this is not a Linked Helper bug. Linked Helper receives responses sent by the LinkedIn server back to the web page. Those responses contain HTTP status codes in brackets which help Linked Helper to understand whether the invite was successful or not. All 4xx and 5xx status codes report errors - list of HTTP status codes - Wikipedia - and would have occurred even if you had invited profiles manually.
- 400 Bad Request - occurs when withdrawn profiles are being invited or when there are too many pending requests
- 401 Unauthorized - most likely you were logged out
- 403 Forbidden - the server is refusing action.
- 429 Too Many Requests - too many requests were sent in a given amount of time. Please, check this article (Incorrect connect response (429)) for more info.
- 500 Internal Server Error - a generic error message, given when an unexpected condition was encountered and no more specific message is suitable.
- 502 Bad Gateway - the server was acting as a gateway or proxy and received an invalid response from the upstream server.
- 503 Service Unavailable - the server cannot handle the request (because it is overloaded or down for maintenance).
The above errors would have occurred even if you invited profiles manually.
For your information, if the contact was already invited before but declined your invitation or you withdrew it later then as per LinkedIn rules, after withdrawing an invitation, you won’t be able to resend an invite to the same recipient for up to three weeks - LinkedIn Withdraw an Invitation.
How to verify the issue is on the LinkedIn side
Please, check whether the profile with such error has Pending status already in basic LinkedIn.
In order to make sure that the issue is on the LinkedIn side, please, try to invite failed profiles via the same platform used by Linked Helper.
In order to do that, please:
- Open the Failed list of your campaign and find the three most recent persons with the same error (LinkedIn error. Incorrect connect response (400)). Recently processed profiles are at the end of the list.
- Open profile page: simply click the profile name and you will be redirected to the profile record.
- Check what platform was used for inviting: find the campaign in the right menu, expand it, and find the platform below the action status:
- Open the profile in LinkedIn: locate "Show in:" buttons and click the one with the name of the platform where the profile was processed by LinkedIn:
- Try to invite the profile manually. If you cannot send an invite manually, then you won't be able to send it via Linked Helper as well.
If the contact was already invited before but declined your invitation or you withdrew it later then as per LinkedIn rules, after withdrawing an invitation, you won’t be able to resend an invite to the same recipient for up to three weeks - LinkedIn Withdraw an Invitation. There is nothing you can do in this case since Linked Helper is not a hacking tool, it can only automate your daily routine actions in LinkedIn.
If you have too many sent but still pending invitations, then we recommend withdrawing most of them and leave only 500 - 1000 pending invites. You can check the number here: https://www.linkedin.com/mynetwork/invitation-manager/sent/. Here is the link to instruction on how to cancel sent pending invites.
If you cannot send an invite manually, then you won't be able to send it via Linked Helper as well.
You can try the software for free during 14 days - download it and activate a free trial.