Excel OLE Error when accessing Excel through LabVIEW

[LV_user1]

Hi All

I have an application wherein I am searching through large number of excel files names (in hundreds) . If the excel file name matches with Pattern provided, I am opening the excel , reading few columns from it and then closing the excel. The pattern which I am providing to look into excel file has upto 1500 permutations.

So in short , I am taking each pattern at one time , checking its availability in hundreds of excel file names and if it is present , I am opening excel, reading stuff and then closing excel.

This works good for some time , however After some time , when my LV application is running I am getting below error popup :

"Microsoft Excel is waiting for another application to complete an OLE action." This popup continues to come at very fast rate and remains there even if I exit LabVIEW.

If I am opening normal Excel file(and not through LaBVIEW) this issue is not observed.

I am attaching VI over here which I am using for reading excel.

[aputman]

The only thing that stands out to me in this VI is that you do nothing if you encounter an error.  You leave references open and you don't close Excel. If this happens repeatedly, you'll end up with many instances of Excel running in the background. 

How is this subVI called?  Can you post the parent VI?

[Ben]

I am leaning toward what aputman wrote and going a bit further...

I think you would be better off opening Excel ONCE before you start looking at the files and pass for Excel into your sub-VI. This should eliminate the need to repeatedly open and close Excel

Then inside your sub-VI, make sure you close any file that was opened regardless of errors etc.

Ben

[LV_user1]

Thank you for reply.

As suggested , VI is now modified to close references when any error is encountered . Still ending up with same error over a period of time.

As suggested by ben, what i understood is i need to open excel application ref once (before for loop), then have this subvI inside for loop(which is how it is called currently to go through each excel file name) and then when all the pattern is matched , exit for loop and close the application ref for excel.

I will check if this works out.

[aputman]

Can you post your modified code?