How to fix the error "There is no application associated with "SiDiary". Run the application first, then open this file..."
If you get an error message on starting SiDiary like "There is no application associated with 'SiDiary'. Run the application first, then open this file within the application." your system isn't installed properly. You can encounter such trouble also when you have installed SiDiary and have used it without any change on SiDiary but on de-installing a completely different application!
The reason is a bug (already confirmed) within Microsoft's setup tool for "embedded Visual Basic" applications like SiDiary. This bug results in deinstalling the runtime module (which is basically needed for any eVB application) although there are still other eVB apps on your device which you don't want to deinstall - but they will stop working and just give you the error from above.
But there's a simple solution: Just re-install SiDiary. You won't lose your data entered before!
There could be the possibility that just re-installing SiDiary doesn't make it run again but in this (really few) situations you can use a freeware tool, VBRegFix, which was especially developed for the Ms setup bug. This tool will fix all inappropriate links in your registry database on the PPC and after executing VBRegFix, another setup of SiDiary it should run in almost every case.
You can download VBRegFix on this website (or if you prefer software portal sites, i.e. Handango.com, pocketgear.com etc.).