There are two types of Citrix connection:

Citrix session: 
A Citrix session is established to either a server or published application.
Up to 6 sessions can be defined.

Citrix Applications Desktop:
This allows the thin client to authenticate against a Citrix server (WEBInterface or StoreFront) and to retrieve the icons for published applications. These icons are displayed on the terminal’s desktop over a secure connection.
When an icon is clicked a Citrix connection is established to the application, either creating a new session or an existing session depending on the whether the second application is on the same server as the first application.

Note: These two connection types can coexist.

The possible scenarios:

1. The screen stays black saying 'Connecting to…' for 20 seconds, then the session closes.
   This indicates that the IP address of the Citrix server is unreachable.
   Check the IP address or routing tables in the AXEL Thin Client.
2. Citrix session closes immediately
   Possibly the TCP port is not available on the Citrix server side (firewall issue using HTTP as opposed HTTPS... ).

All AXEL Thin Clients support ICA/HDX (XenApp)

The key question is which Citrix Infrastructure are supported.

Citrix offers the following types of connection :

• TCP/IP: now considered obsolete, based on UDP,
• TCP/IP + HTTP: a method that uses XML port 80 of a Citrix server (for MetaFrame, Presentation Server and XenApp)
• WEB Interface: method which used HTTP/HTTPS and provides support for MetaFrame, Presentation Server, XenApp and XenDesktop
• StoreFront: similar to WEB Interface but also supports VDI-in-a-Box.

AXEL Thin Client models M80 and M85 support all the above.
AXEL Thin Client models M70 and M75 only support 'TCP/IP' et 'TCP/IP + HTTP'.

Pressing <Ctrl><Alt><i> provides a dialog box that displays information about the current connection : encryption, resolution, number of colors, list of redirected resources, compression...

The AXEL Thin Client model M8X does not have a full browser, but has specific http(s) support to connect to WebInterface or Storefront

WEB Interface
A PNAgent website is created on the Citrix server and the terminal is simply pointed at this website.
The terminal automatically appends the server name/IP address with the default path to find the config.xml file ('/Citrix/PnAgent/config.xml', though this can be overwriten if a non default path is used.)

For example – for non default location :
https://mycitrix.domain.com/Citrix/MonDossier/Config.xml

StoreFront
With the 1236d firmware (or later), the StoreFront connection is supported. Only the server URL is needed:
https://mycitrix.domain.com

With a former firmware, this is very similar to WEB Interface with the additional feature that the client can't automatically locate the StoreFront name. So the full path must be entered. For example if the StoreFront is called "MyStoreFront", the URL to enter will be :
https://mycitrix.domaine.com/Citrix/PNAgent/MyStoreFront/Config.xml

Microsoft servers allow the redirection of certain terminal resources (printers, USB, audio, smart cards, etc). Once redirected the resource is only available to the user of the thin client.

The server contains several drivers for generic classes of peripherals. You cannot add other drivers (Exception: see “other” below)

Note: By default all redirection is disabled. The administrator can specify in the set-up which resources are redirected.

Printer (serial, parallel , USB and network)
Redirecting a printer simply requires that the Microsoft driver for this printer is installed on the server. Just specify the name of this driver at the set up of the terminal.

Smart card reader
The reader must be PC/SC CCID compliant .

Storage devices ( USB flash drive , hard disk , CD / DVD ... )
A storage device can be redirected providing the filesystem is

• FAT ( 12, 16 or 32)
• ISO9660

Audio
A USB audio device must be used (including USB to phono convertors) .
Audio (recording and playback ) is supported by the models 80 and 85 80WMS and Windows 2008R2 server or higher.

COM ports
Serial ports ( AUX1/AUX2 ) Can be redirected to the Microsoft server. They are then seen as standard COM ports . (USB to serial converters are supported

Other
Other devices (webcams, scanners, smartphones, etc) are supported by 'USB port forwarding'. With this method the thin client maps the USB device to a user installed driver on the Microsoft server.
USB redirection is supported by the models 80, 85 and 80WMS.
For RDS/TSE, a W2012R2 server is required.
For Citrix, XenDesktop is required (not supported with XenApp).

Description of the problem
After a changing session, the re-display of the Citrix XenDesktop session does not occur or is incomplete.
Note: This occurs only with XenApp/XenDesktop 7.x and only with a server machine type. (Not with win7 or win8 VM machine).

Explanation
When a session is exited AXEL Thin Client does not save the display. So when the session is returned, the server must refresh the whole screen.
This mechanism is not properly supported by the Citrix VDA component when installed on a server operating system.

Solution
The solution depends on the version of XenApp/XenDesktop:

• V7 : simply enable the 'Legacy graphics mode' Citrix Studio Policy
• V7.5 : migrate to V7.6
• V7.6 : if enabled, disable 'Legacy graphics mode' Citrix Studio Policy
• V7.6.300 : if disabled, enable 'Legacy graphics mode' Citrix Studio Policy
• V7.7 or greater : if enabled, disable 'Legacy graphics mode' Citrix Studio Policy

Some key combinations do not work as expected, for example <Alt><F1> or <Alt><F4>.

Explanation:
The AXEL Thin Client intercepts certain key combinations for its own local operation (eg <Ctrl> <Alt> <Esc> to enter the set-up).
Common key combinations such as <Alt><F1> to <Alt><F6> are used to change sessions. This is why <Alt><F4> does not work in the session, as it is used to hotkey to session 4.

Solution:
Change the session "introducer key"
Enter the AXEL Thin Client Setup and go to [Configuration]-[Terminal]-[Local Desktop] and choose a different value for the introducer. For example change to "Cntl" - than <Cntl><F4> will change session, leaving <Alt><F4> for Windows to process

After log-off, the RDS or Citrix session does not close (a blue screen is displayed)

Explanation:
The session is not closed by the server because there is a process still running, and the process prevent the session from closing

Solution:
The first step is to identify the process that does not terminal with the 'task manager'.
This process must be added to the list of processes that Windows can ' kill ' if necessary.
This list is accessible via the registry. If the process is called 'myprocess.exe', add a REG_DWORD (value 0) called 'myprocess.exe' to [HKEY_LOCAL_MACHINE]-[System]-[CurrentControlSet]-[Control]-[Terminal Server]-[SysProcs].

If the AXEL Thin Client is connecting using “TCP / IP + HTTP” it is necessary to know the XML port used by the farm.

By default this is port 80, but it can be changed.

The value of the XML port can be found in the Citrix Management Console or in the registry: [HKLM] - [System] - [Current Control Set] - [Services] - [Ctxhttp] - [TCPPort].

It is important the XML port setting in the AXEL Thin Client's Setup (default 80) matches this value.

AXEL license ICA/HDX under license from Citrix and re-write in low level machine code.
We select the functions and features that are applicable to our AXEL Thin Client, so we cannot claim to be fully compatible with any specific versions of ICA, but we endeavor to keep the client fully up to date.

For example our current client (March 2014) connects to Citrix version7.5 (including StoreFront)