64 bit - Using 32bit COM addin under MS Office 64 bit

Question

I am struggling to apply an existing 32bit COM addin to 64bit Microsoft Word 2010.

To make the addin visible to Word, I have used the dllsurrogate-method, as it described here.

The problem is that now addin caused some strange exception when tries to add its toolbar and menu to office's. I cannot figure out, what it is, it seems, that the command bar reference became not valid in unpredicable moments.

Can anyone explain this?

Note, that everething is fine when I use the same addin under 32bit Microsoft Word 2010 and more old versions of Ms Office.

Answer 1

32-bit add-ins are not supported on 64-bit. Microsoft recommends to use the 32-bit version of Office unless you run into the memory limitations of a 32-bit process which is only likely to happen if you need to deal with extremely large spreadsheets:

The recommendations for which edition of Office 2010 to install are as follows:

• If users in your organization depend on existing extensions to Office, such as ActiveX controls, third-party add-ins, in-house solutions built on previous versions of Office, or 32-bit versions of programs that interface directly with Office, we recommend that you install 32-bit Office 2010 (the default installation) on computers that are running both 32-bit and 64-bit supported Windows operating systems.

• If some users in your organization are Excel expert users who work with Excel spreadsheets that are larger than 2 gigabytes (GB), they can install the 64-bit edition of Office 2010. In addition, if you have in-house solution developers, we recommend that those developers have access to the 64-bit edition of Office 2010 so that they can test and update your in-house solutions on the 64-bit edition of Office 2010.

If you need to go with the 64-bit version because of the memory limitations you have the following options:

• If you have the source code, you can generate a 64-bit version yourself,

• You can contact the vendor for an updated version,

• You can search for an alternative solution.