Hello Albert,
This will occur if the installation server has a higher version of SAPgui than is currently on the workstation, and the Disable Automatic Workstation Update is not checked.
Refer to 4.9 Configuring SAP Automatic Workstation Update
of the installation guide for more information.
This can be found here:
https://scn.sap.com/docs/DOC-59053
Kind Regards,
Jude