Compile error: mapping null reg

[cholulteca]

I have the following weird error:

Whenever I try to save or compile my vi, I get a message popping up saying "Compile error. Report this problem to National Instruments Tech Support. mapping null reg"
Sometimes it will let me save my work, and then it won't for a while. Another error I have is that sometimes when I try to access the properties of an FXP number input, the whole LV environment crashes. So with those two errors together I keep losing my data.

I am working with LV 8.5 on a PXI RIO card (NI-Rio 2.3.1).

[cholulteca]

I forgot: In the compile error list, it just says the vi couldn't be compiled  (as I am using the german version, I don't know the exact english text)

[Ken_Tobler]

Hello!

Does the error appears also when compiling a simple VI without IO Nodes?

It seams that the LabVIEW Installation had some problem and some components are probably corrupted.
The best thing is to try to repair the installation of LabVIEW and LabVIEW FPGA and if not working to uninstall LV and LVFPGA and reinstall both components.

Best regards
Ken

[cholulteca]

I haven't had any problems with simple vis without any IO nodes so far, but I haven't really tested that.
I'll try the repair option, hopefully I don't have to reinstall the whole package...

[cholulteca]

Repairing the installation didn't help at all. Same problem, when I try to save the vi I get the error message mentioned above (anyway, right clicking the vi in the project explorer and choosing "save" does work)
Trying to compile the vi leads to the error message saying the vi couldn't be compiled.

[cholulteca]

Right now it is working... only thing I changed is the following:
I had a comparison to check if a FXP number was less than 0. 0 was an unsigned integer, and I replaced it with a (1,1) FXP number 0, then it worked.

I'm a little confused, because in the manual it says the "less" function supports the FXP-number type. It doesn't say both inputs have to be of the same type.