Upgrade to 2.1.5 error: blank page and redirect

[Torpedine]

Hello, everybody. I have a problem on a website with the latest 1.12 version. When I call the installation file, the only thing I obtain is a redirect to /cmsms-2.1.5-install.php/index.php, that is a blank page.

Can you help me?
Thanks in advance

These are the system info:
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Cms Version: 1.12.2
Installed Modules:
CMSMailer: 5.2.14
CMSPrinting: 1.0.5
FileManager: 1.4.5
MenuManager: 1.8.7
MicroTiny: 1.2.9
ModuleManager: 1.5.8
News: 2.15.2
Search: 1.7.13
ThemeManager: 1.1.8
TinyMCE: 2.9.12
Gallery: 2.1.6
FormBuilder: 0.8.1.4
CGCalendar: 1.16.1
CGExtensions: 1.53.13
MleCMS: 1.11.4
SEOTools2: 1.2.1
JQueryTools: 1.3.9
CGContentUtils: 1.5.3
CGSimpleSmarty: 1.10

Config Information:
php_memory_limit:
process_whole_template:
max_upload_size: 40000000
url_rewriting: mod_rewrite
page_extension: .html
query_var: page
image_manipulation_prog: GD
auto_alias_content: true
locale:
default_encoding: utf-8
admin_encoding: utf-8
set_names: true

Php Information:
phpversion: 5.6.24-0+deb8u1
md5_function: On (Vero)
gd_version: 2
tempnam_function: On (Vero)
magic_quotes_runtime: Off (Falso)
E_STRICT: 0
E_DEPRECATED: 0
memory_limit: 512M
max_execution_time: 120
output_buffering: 4096
safe_mode: Off (Falso)
file_uploads: On (Vero)
post_max_size: 40M
upload_max_filesize: 40M
session_save_path: Nessun controllo perchè open basedir è attivo
session_use_cookies: On (Vero)
xml_function: On (Vero)
xmlreader_class: On (Vero)

Server Information:
Server Api: apache2handler
Server Db Type: MySQL (mysqli)
Server Db Version: 5.5.52
Server Db Grants: Ho trovato una dichiarazione "GRANT ALL" che sembra essere adatta
Server Time Diff: Nessuna differenza di orario del filesystem individuata

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[DIGI3]

Have you tried the expanded installer?
Have you confirmed your host supports phar?

[Torpedine]

I have expandend the zip and uploaded it on the server. Is there another way?

[DIGI3]

The expanded installer (cmsms-2.1.5-install.expanded.zip) is not the same as unzipping the regular installer. If you read the readme included in the installer, it will tell you the differences and why it's available.