Error description: "cannot complete login due to invalid user name and password" usually occurs after upgrade to vCenter 5.1. Login to vCenter and the web client fails.
I was able to fix the issue in my environment by enabling the NetBIOS over TCP/IP settings in the vCenter server.
Other good practice to follow is to use FQDN for all the hostnames (vCenter/Single Sign-on).
You might have come across the following error while checking for compliance against a host profile in ESXi 5.0 Update 1:-
Specification state absent from host: SATP VMW_SATP_ALUA_CX needs to be set to use Path Selection Policy VMW_PSP_FIXED_AP by default
Host state dosen't match specification: SATP VMW_SATP_ALUA_CX needs to be set to use Path Selection Policy VMW_PSP_FIXED by default
To resolve this issue:-
1. Open Host Profiles page on your vCenter server. (Home -> Under Management click on host profiles)
2. Right click the profile which was giving error and select "Enable/Disable Profile Configuration"
3. In the new window that opens up, expand the storage configuration section and uncheck Pluggable Storage Architecture (PSA) and Native Multi-Pathing (NMP).
4. Hit ok.
After the Host Profile has been modified, attach it to the ESXi 5.0 host again and check for compliance.
Per VMware support, this issue occurs due to a bug in the ESXi 5.0 update 1. This issue has been fixed in ESXi 5.0 update 2 and ESXi 5.1
