I bought Morrowind last night through Steam. I have done all the things required when install MOInstaller.exe (including change the date of .dsa files). However, in the last step, it shows that "there has been an error during opening MGE".

Can anyone help me? I worry about if there is any problem I don't know which leads to this situation.

Render creation error? Or different error post your log here.

what it says is "There has been an error during the opening of MGE. Please make sure that you installed the correct runtimes and frameworks. You can find the link of them in the install guide. Restart the PC after installation. If the problem persists contact the support!"

Okay Edward go into your morrowind directory folder and look for "Log" go into log and go to your error's this is how we can solve your MGE or MGSO problems. Post the log for I can help you figure out what's wrong.

Did you install DirectX 9.0c, Visual C++ 2008 Redistributable and .NET Framework 2.0 before you installed MGSO 3.0?

except .NET Framework 2.0

since when I try to install it, the MOinstaller.exe says that my system is Win7-64 so I do not need to install .NET Framework 2.0

Alright I had this same problem before I posted a thread somewhere, but I learned very quickly form using this http://sourceforge.net/apps/mediawiki/morrgraphext/index.php?title=Installing_MGE_correctly So try this, also if you have to reinstall this go ahead, but I know it take's a moment, just make sure you follow everything correct from installing MCP, EXE optimizer, also make sure you follow everything it say's you must read this to install this correctly, so uninstall MGE or MGSO or which ever one you used. Then reinstall but make sure to download direct x 9.0, Microsoft visuals, and a few other things! Also just make sure you follow the steps, because it's what messed me up the first time thought I could do it and got mixed up downloading the wrong way, other's will explain more, I followed everything it said, so make sure you read clearly how to install this step by step process. If you didn't backup your vanilla files, delete everything that has to deal with MGE or MGSO! I hope this guide helps you out as it did for me!

Errors:
2820...Segmenter: Unparsable line in segment
226....Segmenter: Interdependent fpu calculations
562....Segmenter: Found unparsable FPU instruction
746....Segmenter: Cannot do anything with non memory operands
57.....Operand: Haven't programmed '*' yet
11.....FPU: using uninitialized register
29.....Segmenter: Cannot do anything with non float data values
157....Patcher: Patch to big to fit into code
263....Segmenter: Unable to separate fpu code from segment
50.....Main: fpu code not vectorizable
3......Segmenter: Memory offset is too great
14.....Segmenter: Unable to seperate fpu code from segment
11.....FPU: Leftovers in the registers
86.....FPU: Trying to push an fpu register to the fpu stack
48.....Operand: Illegal offset
8......Operand: unknown register
14.....Vectorizer: Direct assignment
4......FPU: using uninitialized register (0)
1......Segmenter: Blacklisted address
56.....FPU: stack underflow.
1......Code generator: Haven't got reversed v3 input working yet
1......Segmenter: Cannot move instruction with one operand

This is what happen the first time I downloaded this.

exactly same!

I use MGSO_3.0 to install all things(including mods, MGE, etc). MGE is included in this. So you mean now I have to install MGE individually from start? I have delete all things in the game folder and installed a fresh Morrowind.

Yes reinstall this make sure you have Direct x 9.0 Microsoft visuals, netframework 2.0 or 4.0 if your ram is 4gb ram then download the 4.0 version. Start the installation and follow every step, make sure no red error's is around, if you do everything correct your game will look like this. http://i1330.photobucket.com/albums/w566/EzioAuditore2045/MGEScreenshot001_zps37dbea4d.png