NI-488 error after installing 7.1

I just upgraded from 7.0 to 7.1, but I also have 6.1 on my system. Now I am trying to use my 6.1, each time I try to open a file I get the folowing message: Error 7 soccured at Open File+.vi: Open File Possible reasons: LabVIEW: File not found or NI-488: non-existent board. Can anyone, PLEASE, he

determine number of rows in 2-d array

I have a 2d array. How do I determine the number of rows? What if it were an n-d array? Thanks for any help anyone can offer.

Re: capturing one cycle or revolution of a target wheel

Thanks for that part, but how do I know on which tooth of the target I am starting?

capturing one cycle or revolution of a target wheel

I am acquiring waveform data from a test stand, a spinning target wheel. I need to save the data from one revolution/cycle only. Does anyone have any suggestion?

save variant waveform from hardware to spreadsheet file

I am reading a waveform from a teststand (external hardware) into labview as a variant data type. I need to save the data into spreadsheet. Can anyone help? Also, do I specify the path as excel (.xls) or text (.txt) or what? Thank you very much.

zero crossing of noisy signal

I need to compute the zero crossings of a noisy waveform. Can anyone help?