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  • Answer

    If a real computer with the Windows operating system is actually used and no hardware changes and/or new installation of the operating system has been made, the license problem is usually caused by the following points:

    • The mandatory service 'Sentinel LDK License Manager' may be damaged after a Windows update.
    Solution: Reinstalling the driver. It can be downloaded and installed via the following link.

    • The antivirus program blocks the file hasplms.exe.
    Solution: Add the hasplms.exe from the directory to the exceptions of the antivirus program

    • Other security software (e.g. Sandboxie) prevents proper communication of the license service.
    Solution: You can also either add hasplms.exe to the trusted programs or uninstall this software
  • Answer

    Using RFEM or RSTAB, the structures of process manufacturing plants can be calculated very well. The modular structure allows you to configure the software individually.

    Main Programs RFEM or RSTAB
    The main programs are used to define structures, materials, and loads.

    RSTAB allows you to edit and analyze beam, frame, or truss structures. RFEM also provides plate, wall, shell, and solid elements.

    Add-on modules
    Dynamic Analysis
    In case a seismic analysis or vibration designs are required, the RF‑/DYNAM Pro add-on modules provide special tools for determining natural frequencies and mode shapes, for an analysis of forced vibrations, a generation of equivalent loads, or for a nonlinear time history analysis.

    If you have any question about the Dlubal Software programs, please do not hesitate to contact the sales department.
  • Answer

    In the case of a single user license , the user works with the programs licensed to his workstation. Use of the licenses is controlled by a key (USB hardlock, also known as dongle or softlock). The key is installed directly on the computer of the respective workstation. Instead of the USB hardlock, software (softlock) can also assume the protective function. The corresponding authorization file (author.ini) is used to control which programs can be operated with the respective key.

    The advantage of such a single-user license is that the user always has exactly the same configuration of the programs available in the form of a key. No one else can use or block the programs at the same time. Using the programs can be easily transferred from one computer to another, for example, by a USB hardlock. The prerequisite is that the programs have been installed once on the computer with the corresponding authorization.

    The same thing works with the softlock. Here, the relocation procedure is only a bit more complex and can be carried out by means of software. Single-user licenses are particularly advantageous for smaller offices with fewer users who always work with the same software configuration.

    For a network license, the license protection is activated by means of a special network key. It is also available as USB hardlock or softlock. The network key can be attached or installed on any computer that can be reached in the network. A special license manager then controls the access to it. The Dlubal software itself is installed as is the case with the single-user license. The authorization file then specifies that the protection key is searched for in the network.

    The advantage of the network license is that it is no longer necessary to change/move the key from one workstation to an other. Once the software has been installed, it can also be used as long as one license is free and not already used by another user. Another significant advantage is that the respective features of program modules can be better adapted to the requirements. Less frequently used add-on modules can be purchased in smaller numbers than number of employees who have to be able to work with them. The likelihood is low that another employee will use the license at the same time. Thus, add-on modules can also be shared with each other. Due to the option to use softlocks, it is also possible to use them on virtual machines. If network licenses are used, you can also access the Dlubal programs remotely, for example by using Remote Desktop. Since not everyone has a physical access to the server, the license is also better protected against theft, for example, and you do not have to search for it with other employees. 

    Network licenses are now the standard for larger companies with several employees.

    Single-User License
    Employee A works in reinforced concrete area:

    Employee B works in the steel construction sector:
    RF-STEEL EC3, RF-STABILITY, RF-DYNAM - Natural Vibrations

    Employees A also need access to the RF-DYNAM Basis, so they have to get the key from employee B. However, he can not process any reinforced concrete structures.

    Compare network license with the same equipment
    Two licenses RFEM, RF-CONCRETE, EC2 for RFEM, RF-PUNCH Pro, RF-CONCRETE Columns, RF-STEEL EC3, RF-STABILITY, RF-DYNAM Natural Vibrations

    Each employee can use the full range of add-on modules as long as the other employee is not working with them at the same time. The license is only used if the add-on module is open (in use). For example, it would also be possible to edit a structural system with mixed steel and concrete materials. 

    Due to the increased usability and flexibility of the add-on modules, network licenses are associated with an additional charge of approx. 25% of the initial license price (all prices are listed in the webshop).
  • Answer

    Unfortunately, it is not possible to run any single-user licenses on virtual machines. Licensing is neither possible with the USB dongle nor with a softlock license.

    The test or trial version of RFEM 5 or RSTAB 8 is a time-limited version that is controlled by a softlock. Therefore, the trial version of RFEM 5 or RSTAB 8 cannot be tested on a virtual machine.

    In general, it is possible to operate a licensed version of RFEM 5 or RSTAB 8 on a virtual machine. However, you would need a network license for this.

    The same applies to the test versions of the stand-alone programs SHAPE‑THIN, RX‑TIMBER, PLATE‑BUCKLING, CRANEWAY, and COMPOSITE‑BEAM.

    More information can also be found in FAQ 002288.
  • Answer

    Yes, this is possible. In addition to the conventional hardlock dongle (USB dongle), it is also possible to use a softlock dongle. A virtual fingerprint is created for the identification and thus, the license is linked to the computer or to the virtual machine. It is important to pay attention to the properties described under the link below.
  • Answer

    Unfortunately, this is not possible. Both the access via Remote Desktop and the use of virtualization software are planned and blocked.

    The solution to this problem is to use a network dongle. In this way, you can also access the license by using Remote Desktop or a VM. Please inform yourself at our sales department about a dongle conversion.
  • Answer

    If you are using a single-user license (as a student, for example), make sure that you do not try to get access to this license via remote access. Moreover, a single-user license cannot be used on virtual machines. Both cases cannot be covered by a single-user license.

    If you see this message when trying to access a network dongle, it may be due to the server's response time. Copy the hasp_48521.ini file into the folder
    C:\Users\#USER#\AppData\Local\SafeNet Sentinel\Sentinel LDK\
    (replace #USER# with your user name).

    Then, open the hasp_48521.ini file. Enter the IP address of the dongle server as well as the access times (see Figure 02).

    If you access the dongle server via VPN connection, please make sure that the IP address of the dongle server is stored in Admin Control Center (see FAQ 002070).

  • Answer

    The current Dlubal products are released for use on Microsoft-based operating systems. You can install such an operating system on your Mac at the same time. It should be noted that local licenses (hardlocks and softlocks) can not be addressed by using parallel desktops, even if Windows is installed via BootCamp.

  • Answer

    Generally, RFEM and RSTAB are available for Windows only. We recommend to only use Dlubal Software programs on a PC with this operating system.

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If not, contact us via our free e-mail, chat, or forum support, or send us your question via the online form.

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First Steps

First steps

We provide hints and tips to help you get started with the main programs RFEM and RSTAB.

Wind Simulation & Wind Load Generation

With the stand-alone program RWIND Simulation, wind flows around simple or complex structures can be simulated by means of a digital wind tunnel.

The generated wind loads acting on these objects can be imported to RFEM or RSTAB.

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“Thank you for the valuable information.

I would like to pay a compliment to your support team. I am always impressed how quickly and professionally the questions are answered. I have used a lot of software with a support contract in the field of structural analysis, but your support is by far the best. ”