I tried to install IBQ MQ Client 9.1.4 on Windows Server 2019. During installation it asked for domain user account under which service will run. I gave current logged in user, but it failed even though this user is local administrator. It seems the account need some special permission to run MQ Client service.
I searched and found the following article which lists some permissions that are required. Check Table 1 in this article.
https://www.ibm.com/docs/en/ibm-mq/9.3?topic=windows-local-domain-user-accounts-mq-service#q020480___winserviceusrrgt
The exact error screenshot is given below. This is a domain user who is not only local administrator also added in mqm local group which was created by IBM MQ client.
You are not installing IBQ MQ Client 9.1.4. That appears to be IBM MQ Server 9.1.4. The IBM MQ Client is NOT installed using the 'Prepare IBM MQ Wizard'.
Also, why are you trying to use software that is no longer supported? IBM MQ v9.1 went out of support on September 30, 2023.
You should be using IBM MQ Client v9.3 (or v9.3.4).