Hello!
try reinstalling mta, uninstall all MTA files that are normally in "C:\Program Files (x86)\MTA San Andreas 1.6", this will probably solve your problem because the CL23 error is related to core.dll
Try disabling your antivirus Your antivirus or firewall may be blocking or removing the core.dll file.
try downloading another GTA:SA free from modifications of mods etc...
try downloading Microsoft Visual C++, as the MTA depends on libraries provided by these packages to function properly, including the core.dll file.
After installing the libraries and restarting your computer, try opening the MTA again to see if the problem is resolved.
If you need help, just ask .