The following could or would cause error installing:

Using third party software to install ERS98.

Opened applications such as monitoring software.

Opened Internet Explorer and ERS98.

Too many temp files in the Windows\Temp folder.

Installing ERS98 in the Windows directory.

Please don't install ERS98 in the same directory
as ERS32pro.

Note: Install ERS98 in the drive you would like
backups to be saved in.

Note: Don't use third party software to uninstall
ERS98, use Remove.exe found in the ERS98 directory
to remove ERS98.