c# - Problems using Excel Interop in SSIS -

i using excel interop in ssis script task on server excel 2007 installed.

since few days, errors appear when try open script task. whenever open code, references interop marked yellow warning sign , namespace cannot referenced. cannot add again via "add references", , when try add excel object library in com tab, added yellow warning signs (i couldn't find error message that).

however, when don't save changes , run whole project, works without problems. interop therefore seems work, somehow not found in visual studio. tried install primaryinteropassemblies again, without success. interop assembly still found under c:\windows\assembly. strange thing there is, there no processor architecture given assembly, while on development machine. tried uninstall assembly install again, couldn't due insufficient rights (even administrator).

i had install windows sdk few days ago use gacutil, reason missing reference?

the programming language c# 2010 visual studio 2010.

thanks,

edit: found solution, although still doesn't work supposed be. here how works: problem can solved setting "specified version" property of reference false. new projects can use interop referencing under c:\windows\assembly\gac\microsoft.office.interop.excel\12.0.0.0__71e9bce111e9429c\microsoft.office.interop.excel.dll

with bit more of experimenting, found solution problem , want share here. isn't supposed be, , still appreciate if knew reason behind problem.

the problem can solved setting "specified version" property of reference false. new projects can use interop referencing under c:\windows\assembly\gac\microsoft.office.interop.excel\12.0.0.0__71e9bce111e9429c\microsoft.office.interop.excel.dll

i hope helps people having same problems had.

best,