yes, that could be true. I use BLOBs to store text and sometimes that text is empty but should not be null. Today I had the problem, that I have a Query that has a blob file in it and as soon as I call the Edit method, it raises the exception. No chance to put some data into the blob as it does not let my call 

query1.fieldbyname '(theblobfield').asstring without calling query1.Edit first.

I commented out the code in IB_Components that raises the exception and now it works, but I do not know if it has any sideffects. Must be a reason for you put in that piece of code.

If you like, I can show it to you via a Teamviewer session or something like that. No problem.

Just give me some timeslots where you have time. Just notice, that I live in Austria in CET which is UTC+1 and as it is summertime now it is UTC+2.

Best Regards

Helmut