It is very possible that your system has a Microsoft* driver since we do not have a driver for Windows* 8.1 at this time. Besides checking with them there are other recommendations below you may give a try.
Based on the message you get, it is also a good idea to determine if this is happening with other computers or only this one; it is always recommended to restart modem / router once in a while.
I have exactly the same problem
Intel N135 constantly disconnects with the same messages when troubleshooting.
It has a microsoft driver.
I have tried installing intels software but the microsoft driver stays and the problems continue.
All my other wifi gadgets and computers run fine.
Windows* 8.1 will be supported on this adapter. In the meantime you may contact Microsoft* for further assistance with the inbox driver.