2 replies to this topic

[binoco]

Hello!!

I wrote a script function:
function RemoveMySQL(hMSI)
begin
if(LaunchAppAndWait(WINSYSDIR^"msiexec.exe","/uninstall \"" + INSTALLDIR^"mysql.msi" + "\"",LAAW_OPTION_WAIT)< 0) then
MessageBox ("Unable Remove My SQL.",SEVERE);
abort;
endif;
end;


And then, I add custom action to call above function.
If I add it to UI sequence then it's OK. But if I add it to Exec sequence then it's Error when run.

Error content : another installer is running. waitting for it finish.

In my task manager, it has 2 processes of msiexec.exe.

pls, help me!

Edited by binoco, 25 March 2010 - 09:34.

[akerl]

It's not possible to start a 2nd installation from the server process (table: InstallExecute Sequence). MSI follows the ACID rules for transactions. To achive the Isolation state, MSI set a mutex and prevent the second installation process.

[VBScab]

You can't have an MSI execute whilst another MSI is executing. Although you will see more than one instance of MSIEXEC.EXE in the process list, the extras are "server" processes.

Long story short: either build a stub executable which detects and uninstalls MySQL or, if the package you're building is for a new version of MySQL, use the Upgrade table. Appropriate positioning of the RemoveExistingProducts action will either completely uninstall previous versions or perform (what you might call) an in-place upgrade.

Search MSDN for details on the Upgrade table and the RemoveExistingProducts action.