Task Start and Finish date with CSOM gets converted to USA format

Question

I know that this theme was presented at forum, but I can't find answer for it.

I'm setting a task start date using CSOM, and do it using a UK format (DD-MM-YYYY), but Project Server reads it as if it was in USA format (MM-DD-YYYY).

The value gets set correctly in my code, but then Project Server treats it as if it were in USA format. [![enter image description here][2]][2]

I wrote 05/12/2017, the date that appears on the schedule is 12/05/2017. You might think that it's just a viewing format, but other date time project fields are treated correct. This problem is reproduced only for task start and finish dates

What's going on here? Is there a setting in Project/SharePoint that defines how it treats dates after being read from CSOM?

This action is reproduced only for start and finish date, but others project fields with date time type are treated the data correct.

Answer 1

1) Go to Site Settings > Regional settings

Url would be https://sitecollectionurl/_layouts/15/regionalsetng.aspx

2) Here change to local from English (United States) to English (UK).

3) Click OK. If you want all subsites to have the same locale, check the checkbox as below and then click OK.

4) Now check the date format in your list,it should be in dd-mm-yyyy format as in below screengrab.