Symptoms
Presentation Server version 4.5 fails to consume a start-up license, startup.lic, and logs the following Event Viewer error.
Event Type: Error
Event Source: MetaFrame
Event Category: None
Event ID: 9028
Date: 1/28/2008
Time: 3:35:21 PM
User: N/A
Computer: YourPresentationServer
Description:
Your version of the license server on 10.12.x.x is older than the version of Citrix Presentation Server. Please upgrade your license server or specify a license server location with the correct version.
Cause
An older version of the license server for the currently installed product is configured at the Farm Level.

- Or -
From the Server Properties.

Resolution
While the Management Console allows for the operation to complete, thus giving an impression that the server will function as expected, a startup license will not be allocated to the server. This is by design.
CTX112223 – Citrix Presentation Server 4.5 Administrator's Guide - page 78
Presentation Server 4.5 requires upgrading Citrix licensing. If you are running the license server that came with Citrix Presentation Server 4.0, you must upgrade to the latest license server, which is included with Citrix Presentation Server 4.5. Your existing license files are compatible with the new license server.
More Information
CTX112587 – How to Determine the Version of the Citrix License Server
CTX113090 – Multiple Citrix Startup Licenses are Checked Out by One Citrix Product
CTX103625 – Future Access Suite Products May Not Function Depending on the Date in the License File
Presentation Server 4.5 license files cannot be used on a Presentation 4.0 License Server. However, Presentation Server 4.0 license files can be installed on a Presentation 4.5 License Server. Depending on the License file dates and product burn-in dates, Presentation 4.5 User Connection licenses may be allowed by only having Presentation server 4.0 license files on the Presentation Server 4.5 License Server.