FlowVision SC™ FAQ

“Failed to Establish Serial Port Connection” or “Access is Denied” Error

  • This message occurs when multiple programs in Windows try to access the same serial port. For instance, if FlowVision SC is open and connected to serial port COM4, and you try to connect to COM4 via another serial terminal applications (ie: Alicat Serial Terminal, PuTTY, etc.), you will see this error.

An installer error occurs

  • All installers (starting with FlowVision SC version 1.3.18) now distribute a batch file that will run the installer and create a log file.
  • Alicat will need this log file in order to determine what is causing the installer to fail.

License key is “Expired” or “Invalid”

  • The current code is very strict about license keys and will only accept it if it is typed with the exact upper/lower case letters and exact dashes. There have also been issues in the past where copy/paste has caused it to be invalid (because of invisible whitespace characters). It is also a good idea to type it out manually. (Although copy and paste, as long as you are careful not to copy extra whitespace before or after the key, can work.)

Software was upgraded and now it won’t start or it displays errors

Example: Error message of “invalid or unknown” field, item or data.

  • Close the software and navigate to My Documents. You should see an “Alicat_Scientific” folder. Inside of it there will be folders for different software (FlowVision SC/FlowVision MX/etc).
  • If there is a setting configuration that you wish to keep, right click that folder (ex: “Alicat_Scientific/FlowVision_SC”) and send it to a ZIP file, and then send Alicat the ZIP file to have your files uncorrupted. Once uncorrupted, you can delete the folder and replace it with the unzipped and uncorrupted version.
  • If you don’t mind losing your settings configuration, simply delete the folder and start the software again (it will get recreated).

Device not found

  • Check that all Alicat devices have a unique unit ID, so the computer can distinguish them.
  • Check that all devices are powered. A USB or serial port on a computer does not have enough power to power an Alicat device.
  • Check more communication issues here.

FastTrack Ordering

M/MC mass flow meters and controllers that ship in just 3-5 business days.
Standard or High Accuracy
Monochrome, Color, or None
Analog, RS-232, RS-485, or Modbus RTU
MD8, Locking Industrial, DB9M, DB15


2 SCCM - 500SLPM


2 SCCM - 100SLPM

Service and Support

Whether it is time for your instrument’s annual recalibration or your instrument needs a repair or upgrade,
you can fill out the Service Request Form below, email us, call us, or start a live chat session to get the service process started.

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Duiven, The Netherlands