Will updating the project key pattern in advanced settings effect anything in jira

[Bhargavi Vasa]

I have this below format in jira for project key pattern

([A-Z][A-Z0-9]+)

I have tried migrating a project which includes underscore in the project key, so added underscore as below

([A-Z][A-Z0-9_]+)

Now I was able to migrate but after migration is completed it is not allowing me to remove the underscore from the project key format.showing error as a project is already existed with this format

Is there a way to remove it ? Or any way to update underscore any where?

Will removing or adding underscore will effect anything on the instance?

[Trudy Claspill]

Hello @Bhargavi Vasa 

Have you reviewed the Atlassian documentation on this topic?

https://confluence.atlassian.com/adminjiraserver/changing-the-project-key-format-938847081.html

It says:

• If a number of issues have already been created in your Jira installation, then changing the project key format is not recommended. If you must change the project key pattern after issues have already been created, use a regular expression that allows a more 'permissive' project key pattern than the current one (e.g. use a regular expression which will still be valid for existing project keys defined in your Jira installation).

If you want to implement a more restrictive pattern, you will need to first change the project key of the project that currently includes the underscore to use a new key that doesn't include the underscore.

https://confluence.atlassian.com/adminjiraserver/editing-a-project-key-938847080.html

[Bhargavi Vasa]

Is it possible to remove the underscore from the project key pattern in jira

[Nic Brough -Adaptavist-]

Yes, please see what Trudy already said, she tells you how to do it in her answer.