ConfigVersion.cmake does not work with Windows 10

Hi, Some how i can not use find_package under Windows if there is a ConfigVersion.cmake available. For example, when trying to find GTest following error occurs:

CMake Error at test/CMakeLists.txt:4 (find_package): Could not find a configuration file for package "GTest" that is compatible with requested version "".

The following configuration files were considered but not accepted:

C:/path_to_package/lib/cmake/GTest/GTestConfig.cmake, version: 1.9.0 (64bit)

I am using this line to find the Package:

find_package(GTest REQUIRED CONFIG)

i also tried:

find_package(GTest 1.9.0 REQUIRED CONFIG)

But in this case the versions still does not fit.

Running the same Code under Linux works fine. I am using Windows 10 with cmake 3.13.3 but i also tried cmake 3.12.4.

What am i doing wrong?

GTestConfigVersion.cmake

# This is a basic version file for the Config-mode of find_package().
# It is used by write_basic_package_version_file() as input file for configure_file()
# to create a version-file which can be installed along a config.cmake file.
#
# The created file sets PACKAGE_VERSION_EXACT if the current version string and
# the requested version string are exactly the same and it sets
# PACKAGE_VERSION_COMPATIBLE if the current version is >= requested version.
# The variable CVF_VERSION must be set before calling configure_file().

set(PACKAGE_VERSION "1.9.0")

if(PACKAGE_VERSION VERSION_LESS PACKAGE_FIND_VERSION)
  set(PACKAGE_VERSION_COMPATIBLE FALSE)
else()
  set(PACKAGE_VERSION_COMPATIBLE TRUE)
  if(PACKAGE_FIND_VERSION STREQUAL PACKAGE_VERSION)
    set(PACKAGE_VERSION_EXACT TRUE)
  endif()
endif()

# if the installed or the using project don't have CMAKE_SIZEOF_VOID_P set, ignore it:
if("${CMAKE_SIZEOF_VOID_P}" STREQUAL "" OR "8" STREQUAL "")
   return()
endif()

# check that the installed version has the same 32/64bit-ness as the one which is currently searching:
if(NOT CMAKE_SIZEOF_VOID_P STREQUAL "8")
   math(EXPR installedBits "8 * 8")
   set(PACKAGE_VERSION "${PACKAGE_VERSION} (${installedBits}bit)")
   set(PACKAGE_VERSION_UNSUITABLE TRUE)
endif()

Thanks for your help, Thomas