Hi Shafeena, Could you confirm if after your migration, you did not change the values of your OAuth2 credentials in your property file? If you did not change anything in your property file and if the user still exists in your AdWords account, then it should have worked in v201802 API version.
Based on the error description "The OAUth client was not found", it seems that the API user is not existing (or it has been removed) in your manager or client account, or the client ID was deleted in the Google API Console Credential <https://console.developers.google.com/apis/credentials> page. So I can further investigate this, can you provide to me your complete error logs, clientCustomerId and the email address of your API user via *Reply privately to author* option? Thanks, Vincent AdWords API Team -- -- =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~ Also find us on our blog and Google+: https://googleadsdeveloper.blogspot.com/ https://plus.google.com/+GoogleAdsDevelopers/posts =~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~=~ You received this message because you are subscribed to the Google Groups "AdWords API Forum" group. To post to this group, send email to adwords-api@googlegroups.com To unsubscribe from this group, send email to adwords-api+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/adwords-api?hl=en --- You received this message because you are subscribed to the Google Groups "AdWords API Forum" group. To unsubscribe from this group and stop receiving emails from it, send an email to adwords-api+unsubscr...@googlegroups.com. Visit this group at https://groups.google.com/group/adwords-api. To view this discussion on the web visit https://groups.google.com/d/msgid/adwords-api/51a422cc-82b5-4e28-9f6c-81204677ef49%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.