CSOM throwing random error

Occasional Contributor

Hi there!


I've been using CSOM Framework for several months without important problems... Since a few weeks ago, I've been getting "Error 429" sometimes when one of my processes executes. Due to the fact that sometimes it works fine and sometimes it doesn't, I don't know what the problem cause is.


The error I'm getting is this one: System.Net.WebException: The remote server returned an error: (429). at System.Net.HttpWebRequest.GetResponse() at Microsoft.SharePoint.Client.SPWebRequestExecutor.Execute() at Microsoft.SharePoint.Client.ClientRequest.ExecuteQueryToServer(ChunkStringBuilder sb)


For the record, I get this error when I try to see a Resource's assignments.


Thanks a lot.

2 Replies
best response confirmed by Germán Torres (Occasional Contributor)

Hi Germán, 429 normally means you are being throttled - are you making a lot of calls? This article explains throttling in SHarePoint Online which also applies to Project Online -

Best regards,



Thanks for your answer, Brian.


I'll see how I can customize my code so that it doesn't get throttled.