I assume alt-tab moves to the next window. If I click on another app excel grabs it back again. I have about 8 differnet calls for data as info comes form different sources so i guess as each call starts it makes excel the active/foreground app. Each call lasts maybe 5 seconds so essentially i can't use any other app for a minute while it works through them.
I did some digging and saw related issues that involved the follwing solution I have seen this issue before it's "Prevent applications from stealing focus"
Unfortunately i didn't find a solution for Windows 7
You could try something that used to work in XP and sometimes in Vista
1, Go To Start > Regedit
2, Go to HKEY_CURRENT_USER > Control Panel > Desktop
4, Right Click and Click on Export, name it Registrybackup and save it
3, On Right side you can see ForegroundLockTimeout
4, Change the ForegroundLockTimeout value to 30d40 (Hexadecimal) or 200000 (Decimal) to 0 I was a little unclear on the last line, but I tried changing the registry to 200000 and rebooting but hasnt made any difference. I read that shoudl be the default but mine was set to 0.
I have just chekced and it has sreset to 0. This seems a common problem as this guy posted Registry value changing : foregroundlocktimeout, focus, refresh, registry
So I think this is the issue and i need toi keep this registry key at 200000.