The migration of workstations is automatically done by installing an agent (IMAgent service) on these.
This agent is installed by the manager in charge of the workstation migration (IMSrv Service).
Those two services are configured with a startup account that you indicated during the configuration of your migration.
The startup account of IMSrv service must have administrative rights and backup / restore on client computers.
The Access Denied error, generated by the IMSrv, indicates that the client is not "manageable" remotely with the specified startup account from the server where IDEAL Migraion is installed.
The remote administration of workstations requires some prerequisites depending on the type of operating system.
For Windows 7, for example, remote administration requires to disable the Firewall and UAC, and the RemoteRegistry service must be started.
Please see all the prerequisites depending on the type of client:
How to administer Windows XP / 2003?
How to administer Windows Vista?
How to administer Windows 7/8?
A simple test is to open a session with the user used for IMSrv service on the computer where you have installed IDEAL Migration.
Under this session, open Windows Explorer and try to browse the ADMIN$ folder of the worksation: \\STATIONW7\Admin$ - If your client is configured correctly, you should list the contents of the Windows directory of STATIONW7.