Why do I get ASP 0113 / Script timed out errors?

If you have some longer pages, usually with database activity, you may have come across this error: 
 

Active Server Pages error 'ASP 0113'  Script timed out  <file>.asp, line <line>  The maximum amount of time for a script to execute was exceeded. You can change this limit by specifying a new value for the property Server.ScriptTimeOut or by changing the value in the IIS administration tools.

 
A 'bandaid' is to increase the value for Server.ScriptTimeout (see Article #2066). The default value is 90 seconds, so something in your script must be taking longer than 90 seconds. (I do not recommend doing this for your entire site, as the error message suggests, as this may mask other problems for you.) 
 
Now that you've identified a page that takes longer than 90 seconds to run, you need to work on it, rather than simply relying on the bandaid. People want specific answers here, and claim that they "have done the maximum optimized code for our application." Well, if it was optimized, then we wouldn't be here, would we? Unfortunately, there is no simple answer here, since every application is different and can be constrained by different things, from I/O to memory to CPU to bandwidth. 
 
A good place to start on the optimization process might be Article #2424, which goes through a generic set of tips for making ASP pages more efficient. 
 
If you post your code to microsoft.public.inetserver.asp.general, there will be people there who will help you optimize your code.