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LICENSE: Receiving Error R224 Building a Project

Information in this knowledgebase article applies to:

  • C51 Version 8 and later
  • C166 Version 6 and later
  • C251 Version 4 and later
  • MDK-ARM Version 3 and later


We suddenly get Error R224 when trying to build a project. What can cause this?


The most common occurrence of this error happens when more than one user runs the µVision tools from the same PC licensed with a floating license. This is not allowed. If multiple users must use a PC licensed with a floating license, create a single user account for all the developers to share on that PC.

You may also receive this error if an older backup of the FLF file is restored over a newer FLF causing a FLF inconsistency. This condition should be alleviated after each user checks out a floating license one time.


Last Reviewed: Wednesday, October 30, 2019

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