Curious behaviour of a macro with Sendkeys commands

[MartinGM]

I hope someone can help me with this odd behaviour.

I have an Auto_Open macro which runs perfectly in one workbook. It includes some Sendkeys commands (which I dislike, but in this case the alternative is worse !)

In another workbook I have the same Auto-Open macro but with just 2 parts – the first maximises the Excel window and the second part is the SendKeys commands as above. It doesn’t run when I open the Workbook from the Excel jump list – it just sends the “warning” sound and the Workbook dosn’t open. An error has occurred somewhere as a “recovery file” is offered on next opening the Workbook.

It will however run if I open Excel first, then open the Workbook.

It will also run if I suspend the Auto_Open macro with a Message Box before the SendKeys commands.

So I tried a “wait” command (10 seconds – and more) but in this case it did not run.

Not only do I not know what’s going on, I cannot see how to diagnose it !

Any help gratefully received.

[MartinGM]

PS I had earlier posted this in Windows Secrets but there has been no help there. Hence this cross-posting - hope its OK !