Creating a new user on an ESXi 5.x or 6.0 host fails with the error: User name or password has an invalid format

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

Symptoms:

• Creating a new user on an ESXi host fails with the error
  
  User name or password has an invalid format
  
  
• In the %AppData%/Local/VMware/vpx\viclient-x.log file, you see entries similar to:
  
  [viclient:Error :M: 6] YYYY-MM-DD <time> RMI Error Vmomi.Host.LocalAccountManager.CreateUser - 81443
  </time><Error type="Vmomi.Fault.SystemError">
  <Message>A general system error occurred: Weak password: too short.</Message>
  <FaultMessage>
  <item type="Vmomi.LocalizableMessage">
  <Key>com.vmware.vim.host.LocalAccountManager.weakPassword</Key>
  <Arg>
  <item type="Vmomi.KeyAnyValue">
  <Key>reason</Key>
  <Value>short</Value>
  </item>
  </Arg>
  <Message>Weak password: too short.</Message>
  </item>
  </FaultMessage>
  <DetailedMessage>A general system error occurred: Weak password: too short.
  </DetailedMessage>
  <Reason>Weak password: too short.</Reason>
  </Error>
  [ :ShowErr :M: 6] YYYY-MM-DD <time></time> Create User: User name or password has an invalid format

Environment

VMware vSphere ESXi 6.0
VMware vCenter Server 5.5.x
VMware vSphere ESXi 5.5
VMware vCenter Server 5.0.x
VMware vSphere ESXi 5.1
VMware vCenter Server 5.1.x
VMware vCenter Server 6.0.x
VMware vSphere ESXi 5.0

Cause

This issue is caused by one of these issues:

• Special characters in the login name in the Add New User window.
• The password has an invalid format or password complexity.

Resolution

To resolve this issue, view the vSphere Client log message and correct the reported error.

The most common reasons include:

• Weak password: not enough different characters or classes.
• Weak password: too short.
• Weak password: based on a dictionary word and not a passphrase.
• User name or password has an invalid format

Notes:

• The user name can be invalid if it contains a special character.
• The password can be invalid if it does not contain a letter, a number, and a special character.