This is an issue with Steam, your system, or the installation of Forts. Sometimes restarting Steam will correct the issue. Otherwise, please follow Valve's advice here: https://support.steampowered.com/kb_article.php?ref=6218-USFX-5568.

There are also YouTube videos that suggest various techniques to try.

Some people are reporting their antivirus software is stopping the game from starting. In this case disabling the antivirus software or adding Forts.exe to its whitelist allows the game to start.

Feel free to scan any of the exe and dll files in the Forts folder at VirusTotal[www.virustotal.com], which scans them using over 70 different virus detection programs.

Programs that limit access, such as parental control software, may also be configured to prevent Forts from launching.

If Forts closes instantly when clicking Play in your Steam library, but attempting to open Forts.exe directly from ..steamapps/common/Forts/ results in an error message that:

VCRUNTIME140_1.dll cannot be found

You will need to install the latest version of the Microsoft Visual C++ Redistributable. Please go to:

https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170

And install vc_redist.x64.exe (supports both ARM64 and X64)

Normally this is included with Windows and updated with other components (such as Office) but they may contain older versions. And Operating systems that no longer receive updates may need to manually install the latest versions manually.

When this happens access to multiplayer is blocked because it causes desyncs in multiplayer due to the way the anti-cheat system works. Some possible solutions to this problem:

1) Re-install your audio drivers

2)

• Bottom right of the Windows bar
  
• Right Click on the Volume Mixer Icon
  
• Then Troubleshoot
  
• At the end it should say some problem with Generic Audio driver,
  
• Close it, restart the game and that's it.
  
• Should be working

3)

• Open Realtek HD Audio Manager (if you have it)
  
• Open the Speaker Configuration tab
  
• Check 'Headphone Virtualization'

Image here:
https://www.dropbox.com/s/3h09czpf8drao7n/RealtekHDAudioHeadphoneVirtualization.png

Any more information or confirmation of the solution will potentially help other players, so let us know if this helps you or not.

This is most likely out-of-date video drivers. Please follow the links in the 'Slow Framerate' section to update your driver. Contact us if the problem persists.

Update 10-5-23
Support for the Vulkan API has been added in Update 1.22. This feature is still considered experimental at this stage and turned off by default. If Vulkan is supported by your Intel GPU Intel Graphics Support Page[www.intel.com] and you are running Win 10 or later, you can test it out by going into Options -> Video -> and checking 'Enable Vulkan'

Otherwise, continue below for information regarding OpenGL errors on legacy Intel Graphics.

If you have Intel based graphics (integrated or a discrete card) you may see lines of static, flickering, blurring, or other visual artifacts. Notably, these errors are visible onscreen but do not show up in screenshots. These appear to be caused by Intel's OpenGL drivers.

First make sure your video drivers are up-to-date. Intel is continuing to work on improving their driver support for non-DirectX 12 and Vulkan API's and future updates may address this.
Intel[www.intel.com]

If the problems persist the only known workaround so far is to change to non-Fullscreen windowed mode, which also means changing your resolution, and enabling DirectInput in your mouse settings. This will keep the cursor from leaving the game window. If you find your cursor starts interacting with Windows while in Forts, turn off the "scroll inactive windows when I hover over them" Windows mouse setting.

If you have a system with two GPU's, such as a gaming laptop, setting Forts to run only on a non-Intel GPU will avoid the problem.

Some people have also reported that using an external display with their laptop does not result in errors, but this may be specific to dual-graphics devices.

If textures are showing up as large masses of pink hued static, or individual weapons blur and render as blocks when zoomed in, please update your GPU drivers to the latest available version. For older cards no longer receiving updates, if the latest available version still contains errors please navigate to ..steamapps/common/Forts/users/<yourSteamID>/ and open your settings_hardware.lua file in a text editor such as notepad. Then locate the line:

CompressedTextures = true,

And change "true," to "false," then save and exit. This will disable GPU texture decompression.

It has been reported that some laptops will get stuck in a black screen when alt-tabbing, and appears to be related to the use of integrated graphics, especially those with out-of-date drivers. Updating the drivers may correct the issue, but in systems with dedicated graphics the integrated graphics should not be used anyway.

To adjust the settings in the Nvidia Control Panel, right click on your desktop. You should see NVidia Control Panel in the menu. Then click NVidia Control Panel > Manage 3D Settings > Prefered Graphics Processor. If it is set to "Auto" or "Integrated Graphics" we get black screen on Alt-Tab. If we have it set to "High Performance Nvidia" it works as expected.

First make sure your video drivers are up-to-date, according to your video hardware:

NVIDIA[www.nvidia.com]
AMD[support.amd.com]
Intel[www.intel.com]

Sometimes video drivers are not installed properly. This can mean Forts crashes, gets stuck drawing the first frame (a black screen), or it renders in software on the CPU, which is extremely slow. If the software renderer is detected, a message will warn you and open this guide.

For this problem we recommend cleaning off your current driver, then reinstall the latest:

1) Download the latest driver installer for your video card from your vendor (links above).
2) Clean off the old drivers using Display Driver Uninstaller[www.guru3d.com].
3) Restart and install the drivers you downloaded (video resolution may be low for this step).

FreeSync systems can cause low frame rate. We are looking into this, but for the time being we recommend disabling FreeSync if you experience the problem. It may be necessary to disable FreeSync on the monitor, not just in Radeon Settings. You can also disable VSync in Radeon Settings or Forts, but this may cause screen tearing.

If you are still having trouble contact us at support@earthworkgames.com for guidance.

If you experience fps drops in lobbies when people suggest new maps or mods, or when trying to download maps or mods, your Steam download cache may be at fault. You can clear your download cache by:

Opening the Steam client: Steam menu: Settings: Downloads: Clear Download Cache button

This is most likely an out of date driver. We recommend keeping your video and audio drivers up-to-date. See the 'Slow Framerate' section above.

Otherwise, if you still have problems, please download VMMap[docs.microsoft.com] and run and attach it to Forts.exe before dismissing the error message. Save as Forts.mmap and email it to support@earthworkgames.com. We'll reply with further instructions.

If you have the Discord overlay enabled, try disabling it and see if the crashes stop. If not, update your graphics driver using the Clean Install option, if available. If that still fails use Display Driver Uninstaller[www.guru3d.com] to remove the driver, then install the latest one.

Contact us at support@earthworkgames.com if the crashes persist.

There is a system to send crash and desync reports to us within the game and we encourage you to send us everything. In some cases the game will close without the chance to do that.

If this happens to you please send the log.txt file, which can be found by right clicking on Forts in Steam, then properties. Go to the local files tab and browse local files. Navigate to users/<Steam ID#> and you will find log.txt there. Email the file to support@earthworkgames.com with a note about the situation and we'll get back to you.

If you are having difficulty connecting to games in the lobby, Valve have this advice for peer to peer connection issues:

P2PSessionConnectFail error code 4:
- target isn't responding, perhaps not calling AcceptP2PSessionWithUser()
- corporate firewalls can also block this (NAT traversal is not firewall traversal)
- make sure that UDP ports 3478, 4379, and 4380 are open in an outbound direction

This can be caused by the use of forbidden characters in the computer's host name.

1. Press the Windows Start button, then 'Control Panel
   
2. Select 'System and Security' then select 'Set the name of this Computer', or just 'System' if you have icons visible
   
3. Look at 'Computer name'. If there is punctuation in it besides hyphen (-), continue
   
4. Select 'Change settings'
   
5. Select 'Change'
   
6. Edit the name of the computer to remove the punctuation characters
   
7. Select 'OK'

Forts' multiplayer depends on Steam to have the same files between all players. If there is even a slight difference in your files the game can get out of sync, and you could see action unfold differently to the other players.

The game detects when the gameplay is different and sends you back to the lobby, optionally sending a report to us for debugging. It also tries to detect differences in files before any difference in the game happens. This is partly for cheat detection, but also to indicate that something in the data is different and needs fixing. This is called a Data desync.

To resolve this:

1) Right click on Forts in the Steam client
2) Go to Properties -> Local files
3) Click on 'Verify integrity of game files'

At the end it will tell you if any files were fixed.

If you are having frequent Data desyncs when mods are enabled, you can refresh your subscribed mod files by deleting the current versions first, and then following the steps above. These files are stored in your Steam game library folder, within steamapps\workshop\content\410900.

This may be under the Steam client installation folder, or under a secondary game library folder. By default this will be C:\Program Files (x86)\Steam\steamapps\workshop\content\41900.

On my PC I keep my games library on the D: drive, while the Steam client is installed on C:. In this case the mod (and map) files are stored in D:\SteamLibrary\steamapps\workshop\content\410900. If I delete the contents of that folder, and then verify integrity of game files, they will be re-downloaded and will match those of other players.