i find some old problem can not complied now ,but it could complied before. the vc said this has error: PFNGLACTIVETEXTUREARBPROC glActiveTextureARB= NULL; the error is: gl_app.cpp(26) : error C2146: syntax error : missing ';' before identifier 'glActiveTextureARB' gl_app.cpp(26) : error C2501: 'PFNGLACTIVETEXTUREARBPROC' : missing storage-class or type specifiers gl_app.cpp(26) : fatal error C1004: unexpected end of file found why? this code worked very well before.

You have probably changed your gl headers and PFNGLACTIVETEXTUREARBPROC is no longer declared in them..

i update the glext.h but this application uses the old version glext.h which is under the app's dir.