# Do NOT use diacritics in AAD user DisplayName!

Friendly reminder: make yourself a favor and **do NOT use diacritics in the 'Display Name' attribute of your Azure AD users**! 

Why?

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# Problem
- Application installers invoked from the user profile will **terminate immediately without any warning**
- Probably other similar problems related to applications invoked from the user profile will follow

# Cause
- Diacritics in Windows user profile name
 - If AAD user logs in to Windows AAD joined device, a user profile named in the form user-display-name-without-spaces gets created (i.e. user 'Martin Jeřábek' will have Windows profile `C:\Users\MartinJeřábek`). 

# Solution
- From my testing, it seems that it is safe to use diacritics that are part of [Extended ASCII](https://www.ascii-code.com/) table (i.e. it is ok to have a user with DisplayName 'Martin Šek' because 'Š' is included, but 'Martin Jeřábek' will cause troubles because 'ř' isn't) 👍
- To be absolutely sure you don't get into any troubles, avoid using diacritics in the AAD user `DisplayName` attribute completely 🙂 
 - How to replace diacritics? In PowerShell use code `[Text.Encoding]::ASCII.GetString([Text.Encoding]::GetEncoding("Cyrillic").GetBytes('Martin Jeřábek'))`