The servers have been shut down, but this guide contain useful information.

► Install the Flash Player (If you not have it yet) --> Download here <-- [rb.gy]

► Game Updater: Missing Plugin + Login fix --> Download here <-- [rb.gy]

It's an mixed version of the old Heroes Version and the Steam Version. This way its compatible with Steam and portable at the same time. It change the sign-in option from Steam sign-in to Google, Facebook and Uplay sign-in.

Click "Browse" and install it to the "Desktop". Then copy all files into steamapps\common\Heroes
You can also set any other location and play it outside Steam. Thats up to you.

► Game Stopper to quickly stop the game by double-click the file --> Download here <-- [rb.gy]

The guide is categorized into different kinds of problem types that can be encountered.
(such as "server problems", "flash problems" or "generally problems")

First of all, do we need to determine under which problem type / category your statement falls

To determine if it's an flash- or server problem, do you need to follow my Clean Install Guide.
If it not solve the problem, then it's an server related problem (Server connectivity issues)
which will be fixed after the weekly Server Maintenance at 10 o'clock every friday

Generally problems are bugged "plugin loading" or "Dropdown Menue" (unable to select age)

Bug: The plugin can't be loaded, because of an missing configuration that not comes with the installation.

Here's how to fix it:

1) Install the newest version of the flash player. The installer will create an file named pepflashplayer.dll that will be generated unto C:\Program Files (x86)\GetFLV\chrome2

2) Navigate to the game folder where Heroes Online is installed. In my case it's this path:
C:\Program Files (x86)\Steam\steamapps\common\Might & Magic Heroes Online

3) Create an new sub-folder and name it "plugins"

4) Now you have to insert the plugin manually by follow one of this two methods:

method one: Navigate to the path from step 1 and copy pepflashplayer.dll into the plugins folder

method two: Alternatively can you also copy the pepflashplayer32_32_0_0_101.dll from "C:\Windows\SysWOW64\Macromed\Flash" and rename it to pepflashplayer.dll

You can either use the dll from Google Chrome or from SysWOW64 if you run an 64 bit version and from System32 if you run an 32 bit version. (Your bit ver. can be found via "set pro" in CMD)

Downloading the file from external websites like dll-files dot com does somehow not works

5) Right-click the file named package.json and open it in Notepad or any other Text Editor

6) Move the scrollbar to the right until chromium-args and create an new argument option after the quotation mark named
7) Assure that you leave an blank space between the arguments options. Just after the first quotation mark and before the last mark do you not need to leave spaces

8) Now click "Options" in the right panel of the Slim Browser and select "Google Chrome Flash-plugin" instead of the "Adobe Flash Player-plugin" for the best performance.

1) Unistall Flash:
It only unistall basic program elements, and leave log files, Flash Cache untouched

2) Delete log files:
3) Delete Flash Cache:
4) Install Flash
5) Delete Autostarts (optional):
6) Delete Registry entries (optional):
7) Set Flash Updater Windows Service to only update manually

The correct version is important because the developers of Heroes Online mentioned themself that the game is based on flash and that the application is based on Chromium.
(Both mentions can be found at my Reference Source)

Originalmente postado por OFFICIAL SUPPORT:

Why do I need a Flash Player plugin?
"Might & Magic Heroes Online" is a browser game, based on Flash.
Therefore a Flash plugin is needed to run the game.

Originalmente postado por OFFICIAL SUPPORT:

Do I need Google Chrome?
Google Chrome is not needed if Adobe Flash Player (plugin) is installed on your PC. But Google Chrome comes with its own Flash plugin. The game performance of this plugin is better than the performance of the "original" Adobe Plugin (our application is based on Chromium – which is very similar to Google Chrome). For optimal experience, we recommend to install Google Chrome.

►(Comming soon)
Improved nw.exe (Silent Flash Cache Clean before each game start)

►(Comming soon)
Externally Flash (Silent Flash Install which install all necessary files)

► Plugin installer:
--> download here <-- [drive.google.com]
❓What it does? It installs the missing plugin that cause "Couldn't load plugin".
But in order to make it work you also need install the config installer.

► package.json installer:
--> download here <-- [drive.google.com]
❓What it does? It replace the broken configuration file with an fixed config that has the missing configuration which tells the game where the plugin is located at.

Note: Because of Write Protection does the Direct Install fail. But you can copy manually

problem statement: The hidden age window has an size of 170x60.
Unhidden should it has something like 170 x 300 (speculated size)

► https://clb.heroes-online.com/en-US/support