Description:
Unable to load TIBCO ActiveMatrix Administrator UI and encountering the following error in the SystemNode logs:

    TIBCO-AMX-ADMIN-005164: Failed to read this machine model: <TIBCO_CONFIG_HOME>\admin\<ENTERPRISE_NAME>\shared\staging\tools\machinemodel\machine.xmi
Caused by: TIBCO-AMX-INFRA-000193: Machine file at "file:////<HOST>/<TIBCO_CONFIG_HOME>/admin/<ENTERPRISE_NAME>/shared/staging/tools/machinemodel/machine.xmi" could not acquire the lock; it is locked by "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxx"
Symptoms:
Error: TIBCO-AMX-ADMIN-005164: Failed to read this machine model: <TIBCO_CONFIG_HOME>\admin\<ENTERPRISE_NAME>\shared\staging\tools\machinemodel\machine.xmi
could not acquire the lock; it is locked by "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxx"

Cause:
If SystemHost is not shut down gracefully, then the lock acquired on file <TIBCO_CONFIG_HOME>\admin\<ENTERPRISE_NAME>\shared\staging\tools\machinemodel\machine.xmi may not be released, causing the lock issue.

[C - working]Unable to load TIBCO ActiveMatrix(R) Administrator UI with error TIBCO-AMX-ADMIN-005164:Failed to read this machine model

Follow the steps below to delete the lock file machine.xmi.lck, which is in the same folder as the file machine.xmi. Doing so will drop the existing lock on the machine.xmi file and will create a new lock file, once the SystemNode is restarted.

Step 1). Make a backup of the <TIBCO_CONFIG_HOME>\admin\<ENTERPRISE_NAME>\shared\staging\tools\machinemodel\ folder. You can copy the entire machinemodel folder to a temporary location. 
Step 2). Under thw <TIBCO_CONFIG_HOME>\admin\<ENTERPRISE_NAME>\shared\staging\tools\machinemodel\ folder, delete the lock file machine.xmi.lck. 
Step 3). Restart the SystemHost using the following command: tibcohost start -clearCache