Use the Process Monitor tool from Microsoft on the data source machine to identify any processes that have locks on the files. The CRC error might be due to software corruption. Project64 can't open them like it does with zip files.

RAR or 7Z files: Sometimes ROM sites like to distribute N64 games in RAR or 7Z format. So if all the N64 games you downloaded are in zip files, you can load them as is with Project64. It is also possible that a program is holding an exclusive lock for longer than normal, which prevents SDMS from archiving a file, even after multiple runs. Answer (1 of 2): Try using a different extractor such as 7zip or if you already have 7zip, try using winrar or winzip. ZIP files: Project64 can open games from a zip file. If the error occurs repeatedly-for the same files or for different files-on many archive scans, you should increase the scan interval of the Archive Agent template line, to decrease the likelihood of these errors. It is not indicative of a problem in itself. Most exclusive locks on files are held for short periods of time, and on the next archive scan, the locked files should be available for archiving by SDMS. If SDMS happens to open the file for reading during this time, this error occurs. Most programs will lock files for their exclusive access while writing. It is possible for the Archive Agent to read from a file while it is being written. This is a common error message when the Archive Agent reads data files from acquisition machines. Titan FTP supports the ability for the client to verify that a file has been successfully transferred to the server without. If the file is more than 0 bytes in size, it is likely locked by another application. If it is 0 bytes, the Archive Agent cannot calculate a CRC32 checksum for it, and the file is not archived.

How to open crc files