I would rather do more by myself than do more by the customers

The flash component needs to be changed in the project. After the change, the flash component is not renamed, or other operations only replace the SWF on the server. However, many old customers keep leaving messages on the Forum and QQ group, there is still a problem that has been changed before. What is the problem? It was originally caused by the client cache. So the boss said that it is just to let the customer clear the cache directly. However, anyone who has cleared the IE cache knows that this is not an easy task. Although it is not intended for the customer to work hard (only three mouse clicks), if the user has not cleared the cache for a long time, ie is likely to die when you click Delete file ...... This is the user experience .......

Therefore, the best solution is to consider the client segment cache when changing some files, so your first choice is not to change it, but to replace or rename it, in this way, the client browser will not return 304, but 200, when requesting the relevant resources. (Although we have 12 servers that need to be changed, it is not me who is working hard, it is network management ,)

However, according to the actual operation of our website, the mechanism of client cache is not as ideal as described in the textbook. According to the theory, after I modified the file, the lastmodified attribute of the file will be changed. The client browser will automatically request the updated resource instead of using the cached resource. Which of the following solutions can be used? Please kindly advise!