I have installed the latest version 0.75 of Smath Studio on my Windows Mobile device.
I have used the previous version 0.62 on the device before and have created some sheets.
When I try to open the sheet now there is no error message, the name in the window title changes
but the sheet is empty.
Any idea ?

Hello.

This is a known issue. The only way to decide it - to use 0.60.6 version for converting old format file to the new one (this is the last revision of SMath Studio that supports both formats). From ver. 0.62 'old'-format was excluded. The reason of this situation is that the old file-format was very complex and it had required too many lines of unaccomplished code. Sorry for this.

So, you should download SMath Studio 0.60.6 and install it:
PPC: SMathStudioPPC.0_60_6.Setup.cab
PC: SMathStudioPC.0_60_6.msi
To convert the file you want you should just open it with the program and than press 'Save' button. That's it.

Please note: server will advice you to get newer version instead of 0.60.6 ("Requested file is out of date. Use link above to download last version of the file. To get outdated version click here" ), so you should follow the link on the bottom of the download form.

Thank you for the information.
I just wanted a confirmation that this is a file format issue.
I had only created two sheets.
Now with the desktop version available I can quickly reenter the data.
This will be easier than installing the old version and converting the files.