Only 1 instance can be running?
 

i got the right net framework, downloaded eq2map updater and i get this message when i double click the updater icon the first window i get says this
only one instance can be running
so i close that and this window pops up (both are error windows btw)
.Net-BroadcastEventWindow.1.0.5000.03:EQ2Map_Updater.exe appli...
((the above line is the error heading))
(( below is actual error message))
The instruction at "0x00c41919" referenced memory at "0x00000004". The memory could not be read.

Any help with this issue would be greatly appriciated.

This usually results from only installing .Net Framework 2.0

Installing .Net Framework 1.1, should solve this issue.

No need to remove 2.0, just add 1.1 ;)