Remote Desktop Connection Manager (RDCman) does not go full screen anymore

Simpler - just don't maximize the Remote Desktop Connection Manager window.

I just resize the RDCMan window to "almost" maximum size, then hit Full Screen in the RemoteDesktop connection (right click-> Full Screen).

Otherwise, it seems Windows 10 keeps a bottom bar reserved for the taskbar & doesn't allow the remote desktop to go "all the way" Fullscreen.

I know this is an old post but I had a similar problem and found that this worked:

1. Find rcdman.exe.
   Default location: C:\Program Files (x86)\Microsoft\Remote Desktop Connection Manager\RDCMan.exe
2. Open the Properties of the exe (Right click -> Properties)
3. Go to the Compatibility tab
4. Uncheck Disable display scaling on high DPI settings

Click View, then un-check Lock window size.

Here are the steps and settings to make RDCM fit full screen, even over the taskbar, in Windows 10.

1. Right click the server connection > Properties.
2. Display settings tab > Check "Scale docked..." and "Scale undocked..." (I actually just tested and these are not needed for full screen, but I recommend them anyway - I despise the scrollbars).
3. Remote Desktop Settings tab > Check "Inherit from Parent" (This might be variable, start with this to see)
4. Make sure RDCM window is NOT maximized. This is very important otherwise the RDC window will not go full screen when you do the next step (it would still be hidden behind the taskbar and it will have scroll bars, we don't want that). It can be any size window you want, just not maximized.
5. Either of these:

• Right click your server and select "Full Screen"

or

• Press CTRL+ALT+PAUSE/BREAK (pressing this again will shrink out of full screen as well.

Your RDC should now be taking up the entire screen.

This worked for me http://answers.microsoft.com/en-us/surface/forum/surfpro4-surfnetwork/surface-pro-4-windows-10-remote-desktop-other/d17d4321-0f04-4a64-95b4-1c6dd5de9c91?page=1

Here is what I did to solve the issue.  It also works with older apps that don't handle high dpi scaling well. First one must tell Windows to look for a manifest file for an application by default – a registry entry. Next is to provide a manifest file for a given application – the executable file name followed by .manifest.

1. Open RegEdit and navigate to the registry key: HKEY_LOCAL_MACHINE > SOFTWARE > Microsoft > Windows > CurrentVersion > SideBySide.
2. Right-click, select NEW > DWORD (32 bit) value.
3. Type PreferExternalManifest, and then press ENTER.
4. Right-click PreferExternalManifest, and then click Modify.
5. Enter Value Data 1 and select Decimal.
6. Click OK. Exit Registry Editor.
7. The RDP app is %windir%\System32\mstsc.exe so the manifest file is mstsc.exe.manifest.

I can't attach the manifest file so here is the contents:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0" xmlns:asmv3="urn:schemas-microsoft-com:asm.v3">
    <dependency>
        <dependentAssembly>
            <assemblyIdentity 
                type="win32"
                name="Microsoft.Windows.Common-Controls"
                version="6.0.0.0" processorArchitecture="*"
                publicKeyToken="6595b64144ccf1df"
                language="*">
            </assemblyIdentity>
        </dependentAssembly>
    </dependency>
    <dependency>
        <dependentAssembly>
            <assemblyIdentity
                type="win32"
                name="Microsoft.VC90.CRT"
                version="9.0.21022.8"
                processorArchitecture="amd64"
                publicKeyToken="1fc8b3b9a1e18e3b">
            </assemblyIdentity>
        </dependentAssembly>
    </dependency>
    <trustInfo xmlns="urn:schemas-microsoft-com:asm.v3">
        <security>
            <requestedPrivileges>
                <requestedExecutionLevel
                    level="asInvoker"
                    uiAccess="false"/>
                </requestedPrivileges>
        </security>
    </trustInfo>
    <asmv3:application>
        <asmv3:windowsSettings xmlns="http://schemas.microsoft.com/SMI/2005/WindowsSettings">
           <ms_windowsSettings:dpiAware xmlns:ms_windowsSettings="http://schemas.microsoft.com/SMI/2005/WindowsSettings">
            false
            </ms_windowsSettings:dpiAware>
        </asmv3:windowsSettings>
    </asmv3:application>
</assembly>

Copy the above into notepad and save the file with the appropriate name to the same folder as the executable.