Last week there was a problem with user access after a migration between environments. Members of one of the AD groups that had been granted access were not able to access the website or by the MDS Add-in for Excel.
First, I checked the security settings and there was no problem with the configuration. Everything looked OK with each of the security sections. I then added one of the users manually to check if it was a problem with the AD group itself. The user was able to access the model and modify data successfully. The AD group name was spelled correctly, but the scope was set to “Global” instead of “Universal”. Once the AD group was updated all of the users were able to access MDS.