MATLAB: Can’t I open any blocks in SimPowerSystems 5.5 (R2011b) or later

pmsl_rtmcallbackpowerlibsimpowersystemsSimscape Electricalwarning

I recently upgraded my MathWorks products to R2012a. Whenever I try to open a block in 'powerlib', the SimPowerSystems library, no blocks come up and I get the following warning:
 Warning: Undefined function 'pmsl_rtmcallback' for input arguments of type 'double.'
 Warning: Error evaluating 'LoadFcn' callback of <BLOCK NAME>
Why does this happen? This worked fine before my upgrade.

Best Answer

As of Release 2011b, SimPowerSystems transitioned from being a standalone product to depending on Simscape as a requirement. The missing callback has to do with a missing installation of the Simscape product.
Installing Simscape will resolve this issue.
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